It looks like Apple has a sense of humor. Despite a recent episode of The Simpsons that mocked Apple and its chief executive Steve Jobs, the long running comedic cartoon has finally found itself on iTunes tonight.

But don’t get too excited just yet — it’s only the current 20th season that is available right now. And no, it’s not available in high definition. But it’s a start for a show that is near and dear to the hearts of many, as judged from your comments on my last piece about the show being slightly out of touch. (Hey, I liked it too — in 1990.)

It’d be nice to see season 1 through 19 make it onto iTunes eventually, and maybe Apple could even put together a series package deal, so fans wouldn’t have to spend hundreds of dollars to own the show. After all, 20 seasons at what would likely be between $20 and $40 a pop, adds up quick.

Another thing to think about is that each of these seasons, even in standard definition, are several gigabytes large. 20 seasons put together, and you could be talking about a lot of hard drive space — as in over 50 gigabytes. Let’s hope you opted for the bigger version of the Apple TV, or have room on your computer’s hard drive.

Having one popular show from my youth arrive on iTunes also gives me hope for another: Seinfeld. But who knows how much Apple would have to pony up for the rights to that — or if Jerry Seinfeld would even agree to it given his new (and potentially over) role pitching Microsoft products. But whatever, I’d be fine with Seinfeld over Xbox Live too.