I also noted that, perhaps they are in Chaos Side? Well, Terra "should" be because of the puppeter's whell and Tidus... ummm "Join me and you'll have the strenght to defeat your father"... Respect Cloud, Well, Sephiroth and Cloud Allied, well, that, somehow will have sense I guess :/
AH! I almost forgot! In the End when Cloud finally defeat Sephiroth in Shade Impulse he says "The one I really want to meet is..." Could be that Tifa in 012 at the end dies? Just a premature assumption u.u