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It's pretty likely that they won't update the software if they come out with a new one because the hardware will be different.

That said, all we have to go on is rumors right now, and there is no real evidence of it happening soon (despite what Kevin Rose might say). I do think there is credibility that there is a new one in the works, but nobody knows when it will be ready. It could be next month, or it could be next year.

If you are absolutely sure you want the newest one or whatever, and you can live without your current one, then I see no reason not to sell it. It's best to sell as early as possible to make as much money as you can before the prices drop.

If you use your current AppleTV enough that you would miss it, you might as well stick with it until there is a lot more evidence pointing to a release date.

It is really up to you and how you would feel living without your current one.
 
Have you considered the new Mini? I mulled over it for months and finally sold my ATV a few weeks ago and bought a 2010 Mini, best thing I ever did :)

As good as the PS3 and 360 are, the Mini will blow them out of the water doing everything bar games. Whether you want to stump up the extra cash is up to you ;)
 
You also would have to wonder just how much you'd get for a 40GB ATV right now? I think $40 would be generous.

Do you like your ATV right now? If so, why not just keep it? Apple will NOT make the current model obsolete....at least right now. You might see new features arrive that the old ATV can't handle, but you'll still be able to do everything you are doing right now. I see no reason why you still won't be able to rent or buy video and music from now into the next 5 years at least on the 'old' ATV boxes. And heck...if the rumors are true...once your HDD in the ATV goes belly up, a new iTV will only cost $99 which is cheap compared to the price you paid for your current ATV.

Long story, short: No need to sell, you will still be able to use your current ATV for a few more years.
 
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