My main advice is, no matter what BUY AN HDTV for your next purchase. Other than that, get what you can afford and youll love it. Whether its Plasma, LCD, RPLCD or DLP.
And currently the only 1080p sources available are HD-DVD's and/or Blu-Ray. I really don't think the broadcasters/providers will ever offer 1080p. They just got through spending all that $$$ to switch over to digital and get the current ATSC standards met. There's no way in hell they will ever spend any extra change to bump it up to 1080p. However, after all the arguments for 720p giving much smoother images for sports, the argument should be that much stronger for 1080p. So, will Fox and ESPN and ABC ever go for 1080p? I doubt it.
Are both Blu-Ray and HD DVD 1080p? For some reason I thought I read HD DVD was 720p.
The BR advantage is that the format's superior storage (50gig capcacity).