It doesn't appear that MS bought FFXIII.  It seems to have been a business decision alone.  The only rumour is that MS paid the exit fee for a possible exclusivity contract with Sony for SE.  Even then, it must have been in SE's best interests financially to have the game on two platforms than to accept whatever Sony was offering.

If MS had paid for exclusivity, why would it not include Japan where they are finally making some headway?

I seem to remember the same thing on the FFXIII trailers at TGS last year... and look what happened there.

They said that before with FFXIII.

Looking over my post, I don't recall saying that MS bought it (FFXIII).

Do you see in my post where I said that?

i hope it stay exclusive common ps3 need it

I don't know, going multi is good for SE, delaying ready versions to do simultaneous launch isn't, keeping on following this way they could piss Sony users off and for what? Only for MS sake, so, unless MS pays very well, the immediate advantage of the bribe could be nullified. And even if MS pays well,there is a chance that it isn't worth the damage that could arise from getting users disgruntled.

For SW houses the best thing is TIMED exclusives, they can gather bribes for them, if HW manufacturers are ready to pay them, yet being able to milk more money from the game on other platforms when sales on the timed exclusive one fade. If console manufacturers don't pay, sometimes a timed exclusive can still have reasons to exist, for example if the users on a certain platform outnumber the potential others, if the economic effort for simultaneous development is too onerous and/or if simultaneous launch risks causing delays, making return on investment happen later, etc... A successive launch on another platform could also, for example, let correct mistakes that made the first launch less satisfying.

Edit:

Because of my opinion about this matter, I must quite agree with Zenfoldor about the likelihood of WW timed exclusive for FF XIII V.

 ==> I think you are right.

But, in a way, since there are games "Xbox360 exclusive" it is possible to see some games "PS3 exclusive" too ...

so wait and see for me.

Maybe it will be ps3 maybe not who knows but ps3 really need this one after losing final fantasy 13.

Nope... I won't believe it until Hideo Kojima tells me so... and he doesn't work for SE....