Noticing you have Sky who will support HDTV is 2006 try and get one that would at least support HDTV ( 720p50 at least , 1080p50 - though this might be only used for dvd based HDTV material like movies).
So when the world cup is shown in HDTV (more than likely it will be in 2006) you will be able to watch it in HDTV and Widescreen amongst other HDTV services like movies and other sports like Premiership football.