FF15 will defintaley come out this genaration (even if its at the very end like FF12 did), all FF titles since the PS1 era have had a 4-5 production time, who ever is making FF15 has been doing so for at least 3 years now. We have to remember that FF13 was delayed a lot and FF13-2 or v13 are not out yet.
For now I see:
-FF13-2 JP Dec '11, NA March '12.
-VS13 JP April-Aug '12, NA Nov '12
-FF15 JP Dec '12-March '13.
The real question is if SE will do a PS3 and 360 release or a PS3 ,360 and WiiHD release.