Yeah, the OneGuide's pretty cool.
Most of the time I just use my remote control, as normal, but if it's not in reach I'll just give it a bit of "xbox, watch tv. Oneguide. Page down. Page down. Watch South Park" (for instance), and it generally works just fine.
It was still a little bit buggy last time I used it (probably about a week ago). Sometimes it'll try to go to a channel I don't have, and sometimes the shortcuts didn't come up onscreen. But most of the time it's fine.