Immersion Corporation, who you may recall from their rumble-controller suit against Sony, has released a study. Engadget reports that (somewhat unsurprisingly), it indicates gamers will miss the rumble feature in PS3. The 'SIXAXIS' gamepads planned for the PS3 will only have the 'tilt' feature, as far as is known so far. From the article:
"Not only does the (completely unbiased) poll report that 72% of the 1,075 respondents agree vibration feedback enhances their game experience, it goes on to note that 59% of those surveyed would prefer rumble on the PS3 controller, while only 8% care about motion / tilt sensing (sorry, Nintendo). As if these numbers didn't paint a clear enough picture of the message Immersion is trying to convey, two further questions spell it out even more explicitly: when asked if the lack of rumble capabilities would affect their buying decisions ... 5% said that it would definitely cause them not to buy a PS3 and 32% claimed that they were less likely to pick one up for this reason and this reason alone. "