Say, it's been a while since we last checked in with an iTunes Music Store sales update, and that used to be a mainstay in the Apple-flavored melodrama biz, so what say we scope the skinny on the millions tip? (No, we're not sure what that means, either.) CNET corroborates a figure mentioned in that Jobs interview in Rolling Stone to which we incoherently linked yesterday: reportedly the iTMS has now sold 20 million songs since it launched at the end of last April. Why, that's enough to fill 2,000 top-of-the-line iPods! Which is either a lot or not so much, depending on how you look at it.

Now, as you all know, the iTMS represents a whole new way to distribute music, and it's struggling to build some street cred so that people don't look at it as just another hula hoop-style fad that'll fizzle by March. The best way to do that, of course, would be for iTMS sales to overtake sales of traditional physical CDs. The thing is, 20 million songs since April may not sound like a lot when compared to the number of songs Americans buy on CD in a year (10 billion, apparently), but hey, it's still a significant pile in its own right, and a journey of 10 billion steps starts with... um... well, it probably starts with some sort of travel itinerary or something, and maybe a really fine CamelBak, but we're sure there's 20 million steps in there somewhere. And besides, Apple still has over three months to go before its first year is up-- and it only has to sell another 9,980,000,000 in that time to catch up. How hard can that be, right?

Of course, our math's a little rusty, but we suspect that in order for Apple to hit that goal, sales would have to accelerate just slightly.

Let's try to work this out, shall we? As of October 16th, Apple tells us that it had sold "more than 13 million" songs. Just a few days later on October 20th that had climbed to "14 million ." Fast-forward two and a half weeks to November 6th and the total had come to "more than 17 million." And then, as of yesterday, another four and a half weeks of sales had upped the total to 20 million. So after the introduction of iTunes for Windows, it sounds like Apple had been selling roughly 2 million songs a week, then about 1.2 million a week, and most recently maybe 860,000 songs a week.

Waitaminnit-- call us crazy, but those numbers look like they're getting smaller. We're not experts or anything, but that's the general sense we get by looking at them; we'd have to consult a statistician or something to find out for sure. If they are shrinking, though, then we imagine that might be a slight bump in the road on the way to eclipsing CD sales. In order to reach that lofty goal, by our figuring, Apple needs to increase its weekly sales rate just a smidge-- to about 670 million songs a week. By Thursday. Kind of tough if sales are tapering off.

But here's how we can make it happen: by our estimates, if every AtAT viewer commits to buying a mere 40,000 songs each week between now and the end of April, Apple can pull it off! And remember, that doesn't necessarily mean you have to spend $40,000 a week; why, with some albums containing fifteen or even twenty songs for a flat $9.99, you'd probably only have to cough up about $30,000. Okay, maybe $35,000. So get spending!