Internet TV service SeeSaw has launched today after a month of beta testing. The service is available to UK users and offers content from the BBC, Channel 4 and Five. I played with the beta and found the services pretty good, its streaming only so there is no download option but there is a good variety of UK content. At the moment all the content in free but they are looking at a payment model.
The good news for Windows Media Center users is that Martin Milmore has already added SeeSaw as a source for TunerFreeMCE so you can watch the content from the Media Center UI
Download TunerFreeMCE from MadeforMediaCenter.com and the SeeSaw plugin from Milliesoft.co.uk