i'm not gonna pretend that i know stuff about teh cell and blu-ray as i don't know shit. but i do see that many a third party developer are having issues developing multiplat games for the ps3. majority of the multiplats are slightly better or even significantly better on the x360 than the ps3.
though the cell is a very capable processor as proven by the likes of uncharted2 and killzone2, its complexity to code for is a hindrance, and no its not that the developers are lazy, imo, its more on the fact that they are timed constrained and are on a budget. not enough time and not enough cash to get the games properly done for the ps3.
on the otherhand, larger storage space of the bd allows for more content and longer games. which is why i'm quit disappointed with gta4. if it had been ps3 exclusive it could have been larger and hand more content.