i think that the greatest news for x360's owners is that the consoles confirms once more to be highly profitable for 3rd party developers ....ok, the HW sales have been decreasing in the last months, but SW sales have remained strong and thus the decision of not releasing a game for x360 is not an easy one for a 3rd party.
we all know that developing an A title for X360 or Ps3 might cost a lot of money and till now apart for some notable exceptions i think that a 3rd party developers have made money only out of x360 (= at present Sony has to pay for exclusives much more than MS).