We recently bought our son a TV with the stuff you describe (internet streaming video device), as like you, he has internet/wireless, but no cable. He loves it! Especially since they were watching movies on the computer screen, which was a pain for 2 people.
I have cable, but none of the "extra" channels, like HBO. DH keeps threatening to cancel the cable, but I do watch the Tour and other bike races on VS, as well as CNN, and let's not forget HGTV.