Nope. Lets not overestimate the 'value' of rumble with regards to the actual purchase; its not an option that is a deal breaker with or without. It only becomes an issue when people 'miss' it when playing.
Since motion sensing so far in the PS3 seems to be truly "gimmicky" at best (unlike the Wii)...and this is speaking purely from an execution standpoint, not technology...its up to the developers to do interesting things with it...anyway, MS's only competition is the Sixaxis in that regard (Wiimote is dedicated technology unlike the ancillary motion sensing in an otherwise fully functioning 'standard' controller), MS shouldn't be compelled to IMHO.
On a side note, I played with those controllers that have fans in them cooling your hands, and that is a surprisingly pleasant feeling.
