of course there will be universal players in the future. even if paramount and universal switch sides this week. why? because there are about 1,000,000 potential customers out there who own hd dvd's now and will have hd dvd playback on their list of requirements for their next player.
if denon or pioneer can spend $25 in parts and licenses to make their next bd/dvd player a bd/hd dvd/dvd player, you think they won't add it to the spec sheet as a matter of course? (remember, bd gives you the blue laser, dvd gives you the optics, and sigma will probably sell you the SOC cheap

).
they won't call it a dual format player...they'll just call it the new universal player, and every manufacturer at the mid level and higher will join them so they don't lose the "battle of the spec sheets."
everyone will require bd/dvd/cd playback. but also, some people require sacd, some require dvd-audio, some require hdcd, some require mp3 playback from dvd+rw, and now some will require hd-dvd playback. adding support is easy, and the marketing dept will demand it.