I wouldn't mind seeing him again, My Dogmeat died in FO3. :cryvaultboy:
Mine too, mine died quite a few times but I just kept reloading old saves.
Then he died during the final battle helping me fight super mutants, so I took that as his real death and went on to finish the game. Alone.
The dogmeat in NV could be the same dog as the one in FO3, dogmeat in 1 and 2 were the same dog. I wouldn't mind if it was another dog though, As long as it was called dogmeat.