SE's been working on XV for years anyways so that game must definitely be out before KH3. I mean, with one KH game coming out every year to keep us distracted waiting for KH3, KH has enough. XV on the other hand must be out ASAP.
As much as I despise KH2 with a burning passion, I'm looking forward to 2.5 simply because it means KH3 is on it's way. Also, KH trophies to plat so why not?
As surprising as this is, I don't care which it's for, as I'll have both by the time it's released, however it's probably better to put it on PS3 at this point simply because more people have PS3's at this point.