What could possibly cause a half-a-year delay for a new Apple TV?

Apple news sites lit up on an otherwise quiet Wednesday with rumors that Apple will unveil a new Apple TV by April, but won't sell it until Christmas. Though it was widely reported throughout the Apple blogosphere, the sole source for this was a report published today by Bloomberg:

Apple Inc. (AAPL) is planning to introduce a new Apple TV set-top box as early as April and is negotiating with Time Warner Cable Inc. and other potential partners to add video content, according to people with knowledge of the matter.

Time Warner Cable is an easy target for this sort of rumor. There's already an app for the Xbox 360 that enables Time Warner Cable customers to watch content. It's been out since last year. The app lets you watch video on demand and live television directly through your Xbox 360, without having to use a set top box as an intermediary device (though you still need to be a Time Warner cable and internet subscriber). It's entirely conceivable that Apple's working out a similar arrangement to bring that functionality to the Apple TV.

Of course Apple is working on a new Apple TV - they revise and refine products all the time. What's more, the evidence is there that Apple is planning a new Apple TV, and it has been there for a while. The timeline supports the idea too - It's been two years since a major change to the Apple TV (the third-generation box was given a minor revision last year).

Then there's the time frame - the Bloomberg piece suggests that Apple will announce the new Apple TV in April but won't ship it until the end of the year (they hedge their bets saying that's subject to change because of negotiations with content providers). I can't see a delay like that happening. People buy lots of Apple TVs. The Apple TV is the most popular streaming video box on the market. The Apple retailer I spend my weekends in often has trouble keeping them in stock.

If the rumor is true that there will be a delay between the new Apple TV's introduction and its availability, this wouldn't be the first time Apple's announced a product months before shipping it. Apple previewed the new Mac Pro in June but didn't ship it in December, and they pulled the old model from circulation. But the Mac Pro was a low-volume seller to begin with, and regulatory changes in the EU killed that market completely. The original iPhone and Apple TV were both announced months before they shipped, too - but they were entirely new products for Apple, not replacements for an already-popular device.

It's been rumored that you'll finally be able to play games or run other apps on your Apple TV instead of just passively viewing content channels. If it were necessary to get developers on board to create apps for a new Apple TV, I can understand a delay. But a half-year delay? Unlikely. For Apple to announce an Apple TV in April but not ship it for six months or longer would kill a decent revenue stream - Apple sells millions of Apple TVs ever year.

I just don't think the math works.

What do you think? Would Apple actually announce an Apple TV then wait months to release it? Or is it a shorter delay more likely? Share your thoughts in the comments.