They wont alienate Multiplayer. Thats where they have always shined.
Nintendo already saw how horrible of a mistake it was requiring 3-4 GBA's for FF Crystal Chronicles. They surely wont be making the same mistake twice with Revolution.
Now...if they gave a huge incentive for playing a game with multiple Revolutions wirelessly linked together or something, that would be awesome. As long as it doesnt say "Requires 2 or more Revolution consoles" (replace Rev with whatever Ninty renames it to
)