I've got DVB-T HD working with DVBViewer OK. However, on my 3GHz P4 the decoding is too slow. CPU at 100% for 1080i on TV3.
Curently using the codec which comes with Twinhan digital TV (which is a version of the PowerDVD codec). Seems to work fine at least with s/w decoding. Geekiegeek has reported that he has got this codec working with h/w acceleration as well.
I've got an 8500GT GPU which supports hardware H.264. If I can get the h/w decoding working, I think all should be sweet on my PC. I know that you can get this working with Vista and EVR with the PowerDVD codecs. I think you may also be able to get it working with XP as well. Seems you need a non offical ForceWare XP driver 165.01 for the Nvidia GPU. See this link:
Anyone tried this yet? Want to give this a go before I fork out yet more money for a Vista upgrade.