So far I think it's only possible in DKCR2 to have DK pair up with either Diddy, Dixie or the new / old / 4th helper Kong. So no, I think Diddy and Dixie will both be standalone characters. Even though I'd totally accept a Diddy and Dixie duo IF they'd be able to pair up in DKCR2.
So far, DKCR2 >> Smash for me.
I dunno, yesterday I felt very meh for Smash, but little by little that hype is really starting to build up. This E3 was GLORIOUS. SO MANY GAMES!!!
It'd be cool if you tag out between all 3. As in have Dk+Diddy, DK+Dixie, and Diddy+Dixie for old times sake.
But I wasn't saying that because of the new DKC, though Dixie coming back could hold some Smash significance. It was simply because Sakurai as always will try to reinvent the wheel and try new things. There's nothing saying he won't try to pair them up again this time around. Last time it was due to technical difficulties, but maybe he managed to breach with Namco's help.
Oh, and I have a hunch that one of the newcomers will be the guy from Wonderful 101, either him, or his team of the 4 lead characters as a sort of Tag Team.
Oh yeah, and DKCR2 and Rayman Legends seem like the goto platformers of next gen. Super Mario World Nyan was very meh for me.