Blackberry may be coming out with their own version of an AppleTV like device at the end of October so you may want to wait (codename Cyclone). My guess is it will be announced at DevCon if it is going to come out. Possible that PB may be able to stream to this device. If it can play Netflix I'm ditching my AppleTV2 for one of these devices.
I liked the idea of apple tv, so much so that I bought it.. Then I never used it so sold it again. Without jail breaking it, they are so limited.
I built myself a micro pc which is about the same size as the playbook box for about �190, allows for streaming of all wireless devices I have at 1080p and is just as good at streaming internet content.
If rims project was an open source non restricted product then it would be worth an investment