What about the WAF?
or Wife Approval Factor.... how well will the family get on with accessing these services in from of the telly, and from what I have seen, not very well yet.
An issue with a lot of these is that you cannot access them from a single unified frontend, although XBMC and Boxee come close. I'm a long running Mythtv user, but it has very limited support for streaming services like these especially UK based ones. The wiki entry for netflix advises running a virtual XP machine on your myth server.
Really don't want a windows box under the telly - Got a plan for a Raspberry Pi running XBMC velcroed to the back, when I can lay my hands on one for a sensible price.