Sony isn't profiting off the PS3 as far as I am aware. And certainly wouldn't be if they had to make a price cut anytime soon. The division made a profit last quarter on holiday based PS2 and PSP sales.
A price cut would benefit Microsoft a lot. How much? Who knows.
I really don't know about NATAL, could be a wildcard.
Furthermore, Microsoft has literally one of the most stunning game line-ups ever seen this year, almost akin to their dream year a couple of years back.
starcraft - Playing Games = FUN, Talking about Games = SERIOUS