Yesterday, after the close of trading in the big US stock markets, Apple announced amazing quarterly results. The stock price, which had already climbed a few dollars earlier in the day, responded by climbing an astounding $11 dollars further in after-hours trading. Best of all (for Apple investors and fans), the value held through today’s trading, closing at an all-time high of $187/share. Yowza!

And then after hours today, the stock seems to be back down $11. Ouch! The roller-coaster ride of Wall Street can be harsh, but $174 is still a healthy price by most accounts. Anybody who bought a few short months ago at $130 is probably feeling pretty good about now. [Update: Don’t know if it was stale data I was getting, or if it really did dump to $174 after hours, but as several people have pointed out, it now seems to be back up in the $180’s.]

Apple’s good fortunes outside of the stock market appear to be a lot less volatile. They keep building amazing products, and more and more people keep buying them. John Gruber’s analysis today focuses on the huge increase in Mac sales this past quarter, which he chalks up to the conventional halo-effect argument, and elaborates on other market factors that may be boosting sales.

As I said, I own stock in Apple, Inc. So it’s super great news when Apple’s fortunes increase. But I’m also an independent developer for the Mac, which means I own stock in Apple’s customers, too. If Apple’s stock was just going up, up, up with no particular explanation, that would be one thing. But it is going up at least in part (I speculate) because they’re attracting so many new users to the Mac, and there is no clear sign that this trend is slowing down.

When Apple doubles the market share of the Mac, it stands to reason that the size of the group of people looking to buy third-party Mac software also doubles. Hooray for indie Mac developers — the size of the crowd walking past our storefronts is getting bigger and bigger every day. Perhaps my analysis is simplistic, but it seems obvious to me that more people are therefore going to stop in and check out the merchandise. We all win. Thanks, Apple!

It would be enough to cheer about, this booming population of Mac aficionados. But that’s just the Mac. The stock price is also rising on news of iPod and iPhone successes. And what do you know, with Jobs’s recent announcement of an iPhone and iPod developer SDK, it looks like indie Mac developers are invested in those customer bases as well.

Whether you are invested in Apple’s stock, its customers, its products, or all of the above, this is an incredibly fun time to be passionate about and involved in Apple’s future. A great time to be invested in all things Apple.

Anthony Cole over at Macteens interviewed me for the online magazine. In it we discuss my time at Apple, my decision to strike out on my own as an indie developer, and MarsEdit’s so-called competition.

Thanks for the interesting chat, Anthony!

The buzz in the Mac community is all about Leopard. It’s coming next week, and many users are rightfully concerned about whether their favorite apps will “just work” with the update.

I think some users are surprised to learn that many indie software developers take it for granted that “working with the next OS release” is a given, barring some extremely costly circumstance. Extremely costly circumstances include situations where, as with the debut of OS X, applications needly to be significantly redesigned or retested. For the version bumps in major OS X upgrades, developers should be happy to give free upgrades, because the updates bring so many new features to the developer’s tool kit.

OS upgrades are Apple’s greatest gift to developers. We want users to upgrade. So we should support the upgrades in our software, for free, whenever possible.

I get emails from users who have clearly been given the raw end of the deal by other companies, and I can’t decide whether I have more pity on the user or on the company that thinks it’s winning anybody’s heart by nickel-diming its customers. Just give them an update, already!

Enough Preaching – What About Red Sweater?

I’ve been running pre-release versions of Leopard as my main development OS for over 4 months, and I’ve been using and testing each of of my apps in that environment. Fortunately, the vast majority of things “just worked.” I had to make some minor tweaks to FastScripts, which I released with the last update.

Red Sweater applications are Leopard-Ready (as far as we can tell), and if any compatibility issues do come up, I expect to be able to address them quickly after Leopard is publicly released. If you’re thinking “I hope my favorite Red Sweater apps will keep working when I upgrade to Leopard,” chances are overwhelmingly good that they will.

Thanks for being my customer! Leopard is going to be awesome!

Update: It’s easy to forget, but it should go without saying that the ease with which my applications were migrated to Leopard was made possible by the hard work of hundreds of Apple employees who worked their asses off these past two years.

Today is apparently some kind of Blog Action Day for the environment. I don’t know how legit it is – I didn’t hear about it until today, and I’m not normally much of a “joiner,” but in my opinion it won’t hurt anybody if I talk a little bit about the environment.

I am not particularly educated about it, but I care about it. I confess that I leave most concerns to other people who are dedicated to the science of preserving it. Because I’m not particularly skilled or knowledgeable, I figure it’s not my business to spend too much time thinking about it. But I do spend time worrying about it.

I’m convinced that climate change is real, and it scares the bejeezus out of me. Many of you agree with me, so I’m not talking to you right now. I’m talking to those of you who don’t agree, or who are on the fence. Those of you who believe it’s an overreaction, or that it’s a deep liberal conspiracy. Who am I to tell you you’re wrong? After all, I just admitted I don’t know all that much about the environment. But still … what if you are wrong?

Say you live in a village that just happens to be situated under a large dam. If the dam breaks, the village dies. If the dam stays, the village lives. Half the village is convinced the damn needs renovation. There are small cracks and a tiny amount of water is leaking through. Some experts say the small cracks are indicative of a larger problem, and eventually they will turn to large cracks, before giving way completely and flooding the town. Others say it’s poppycock, and the dam is strong as ever.

So the village is left with two choices. Fix the dam, perhaps at unwarranted expense, or leave the cracks and hope for the best. When it comes to consequences like wiping out the village, I believe giving the benefit of the doubt to the worried half is worth your consideration.

What motivates the deniers of climate change? For some I’m sure it’s a momentum thing. They know a lot of people who are against it for possibly politically allied reasons, and so they go along with it. Truthfully, momentum and trust are large parts of the reason for my being convinced to believe it. For others I suspect a deeper psychological reason: they’re afraid like I am, but it’s easier to rationalize the problem away.

What makes me particularly comfortable with the idea of “doing something” about the alleged problem of climate change is that the prescription for the cure has positive benefits in any case. Reduce air pollution? We can benefit from that even if there isn’t a causal relation to climate change. So let’s use this potentially catastrophic situation as an excuse to clean up the air. We’ll have happier lives and if we’re lucky we might just save the world while we’re at it.

Update:I shut off comments because, as could probably be predicted, it is turning into a debate between pro and con readers. It’s not that I don’t think you all have a right to your opinions, but more and more the comments were debating the finer points of other readers’ opinions, not mine. Well, it’s my blog and I take seriously what you all have said in response to my thoughts. I think the comments that have come in so far do a good job of representing two sides of the issue, so there probably isn’t a lot more that needs to be presented here.