Looks like the latest XBMC 12.0 will have Raspberry PI and PVR support
http://lifehacker.com/5960829/xbmc-120-frodo-beta-brings-live-tv-pvr-support-and-more-to-your-media-center
http://lifehacker.com/5960829/xbmc-120-frodo-beta-brings-live-tv-pvr-support-and-more-to-your-media-center