In other news, the sky is blue.
I don't see what there is to discuss, really : Microsoft has tons and tons of cash to throw around to secure some third party exclusives, and now that Sony is financially fragile, there is no sense for them (Sony) to even try to compete on this front.
I think publishers have seen what happens when you try to build a new IP for a next gen and have the first installment as an exclusive- it ruins profit potential for the next few games. (See: the big gap of sales for the Bioshock series on PS3 vs Xbox, Mass Effect, etc.).
Heck, the major exclusive they nabbed with Rockstar ended up being a wash for them, as Take Two mentioned in a quarterly call that financially it wasn't worth it in the long run since it kept the team busy with small chapters when they should have been working on GTA V.
I think the exclusives will be for the games that don't rely on series growth (like the multi-only Respawn game that's rumored to be exclusive) but I think the age of major 3rd party exclusive games might be over. Instead of "and you can play it only on Xbox" you'll likely hear "and you'll be able to play it first, only on Xbox." We'll see.