Well, while we're on the subject I thought I would toss my two cents worth in on AppleTV. I agree, there is a lot more it could do, and it has had it's quirks. I think Apple has been putting most of its resources on the iPhone/Touch, then Mac, and finally products like ATV.
Here is my want list:
Allow ATV to sync with iCal. I would love to see my calendar for the day much like a hotel TV calendar of events channel.
Rent a TV program as mentioned previously. I really don't need to own a lot of the TV programs I am interested in. Just catch that one or two I miss or don't see because of work. Yes I know I can by a DVR, but I don't watch that much broadcast/cable TV.
Sports scores. Ok not a big deal, but I have a widget on my Mac that does this, why not ATV?
And as I mentioned in a previous post - a DVD player which plugs into the back of it, and sits under it maybe with a extra fan for all that heat
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It would be a nice convenience add on.
And I do like some of the other suggestions listed in this thread as well.