Because after a few years of "settling in," Sony is finally ready to spread it's wings in the next generation of consoles. Or at least that's the excuse they came up with for the last E3, but I'm beginning to believe they really don't have some sort of "master plan" and are really just going through every exclusive they can hold on to in the hope that they'll find one that will sell their system.
The climate has changed though. Sure, exclusives are an important selling point for systems, but more and more games are dropping exclusivity, possibly because companies know that will sell more copies. Microsoft has been smart in buying up exclusivity of DLC, as it gives its version a deal-breaking edge whenever a decision over which version to buy arises. Further, Microsoft has established a much friendlier and accessible online system. And even though it is nice that PSN is free, I must admit that in some sick, twisted way, charging for an online system gives it a sense of value (and also a set of standards to live up to). Not to mention, on a rather contradictory note, that the Xbox 360 has more good online games than the PS3.
But now it's Sony turn, or at least that seems to be the general sentiment. However, running through the thread, I've only encountered three exclusives for the PS3 that anyone seems to care about. I myself am only truly interested in God of War 3 (although I will admit I do wonder how inFamous will turn out). So, they're releasing a few exclusives, only one of which I can really be sure will be any good. I really don't think that constitutes a "field day" for the PS3.
Granted. this is rather hard for me to say, as I myself own a PS3. Something's definitely gone wrong when I've had the system for six months and only felt compelled to get two games for the system. I will admit that MGS4 was excellent and LBP was good, but combine the two and your lucky to get 30 hours out of the experience. There was no reason to get anything else for the system, as there are no other interesting exclusives and I'd rather play all the other games on my 360 for a myriad of reasons.
So I can't agree that "all the good exclusives are coming out for the PS3," but I do wish they were, if for no other reason than to redeem my choice in getting the system.