Heh, never thought I'd have to make my very first post on my SoSH lurker account to talk about Android Hacking.
Has anyone actually got MLB.TV working through At Bat on the Nook? I've had no luck with either CM7 or running Froyo. Tried spoofing build.prop to be a Tab, which is supported, but no dice.
It seems to read the device type and only show if it is one of the supported devices. (Only the ones listed in the market description.)
There are people asking on XDA and other places about the Nook and other devices, no clear solution yet.