Could they not bring out an additional device somewhere between the two? If I'm going to have to buy an ATV as well as a TC then I won't bother. The ATV only has one HDMI port as I understand. So currently, you have to buy two devices to stream different parts of your iTunes library to TV and stereo - at least that's how I understand it.
In another thread, there was much discussion about how since this new TC is rumored to be built upon the same A4/A5 hardware platform, and if it is going to be able to be the central storage of all iTunes media, why not just add an HDMI and digital optical audio port to make it a new

TV too? If you think about the software as just "apps", the

TV software would just be another app running on this platform.
Those with more than 1 TV could still buy an updated current version of the

TV without all of the TC/AEBS functions.
Personally, I really like the idea of Apple adding on the 2 ports. I could store my replacement TC/

TV hybrid near the TV as easily as where I store the AEBS now. But, I don't expect it to happen. If not, yes, if someone wants to centrally store their iTunes library on this rumored device AND stream from that to their HDTV, they would need both this replacement TC and an

TV.
But rather than fret much about it, it might be a good idea to just wait until tomorrow and see what we get. With the news that the A5 can output 1080p and the current gen of

TV still capped at 720p, the

TV is also due for an update. My guts say that won't be tomorrow (a hardware makeover that is) but I would expect it in the usual event this Fall.