steeleez, the HD DVD/BluRay markets are very new at present - the players are not very refined and the list of titles available on each format is relatively small. If your happy with that then the new formats offer picture and sound quality far in excess of what DVD offers and will push a HDTV plasma to it's limits.
What sort of budget are you looking at for your purchases? You're obviously buying a screen so that should be your major concern at present (IMHO). I would suggest seeking advice on the
Plasma Forum. I would say HD DVD and/or BluRay are purchases post that. Just state when asking what panels to go for that you intend to use high def sources and look for HDMI connectivity (preferrably at least two sockets).
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