Setup was a doddle - given the WiFi key it connected, downloaded three patches and was ready for action.
It instantly picked up the local UPNP server at both Hugh's place and when I got it home, and played music and video without any problems.
The YouTube app works, the Google Maps app works, and it generally "just works".
Not had much of a chance to test out music stuff, as Julie's crashed out asleep. But I shall give that a proper try out in the next couple of days.
The only problem with it so far is that it requires you to have a UPNP server rather than running directly from a windows share. So I'll have to get around to setting one up properly soon, as my current NAS doesn't do that. But in the meantime Windows Media Player will do a pretty good job - or I'll use TVersity, which is also free.
For £50 I'm very glad I picked one up.