I'm a bit curious, which Norse myths are the new legendaries referring to? I KIND of get Xerneas, because it apparently is in reference to Yggdrasil, in which four stags ate among the branches.
But what is Yveltal in reference to?
RE: So, the music: Is it orchestrated?
I wouldn't be surprised to hear a couple of orchestrated songs in game (Champion battle and legendaries more than likely). But the chances of the games being fully orchestrated are very slim.
Street Pass functionality- Mystery Gifts, etc
Spot Pass Events- Special Pokemon, Tournaments, Challenges
If X and Y represent chromosomes, then maybe hybrid breeding.
Training mini-games designed to boost EVs.
GameFreak has had the 3DS dev kit longer than anyone, which leads me to believe that they've been working on these titles longer than we may think. While we were all speculating about 3D compatibility for Black and White, they probably already started working on X and Y.
Pinser Evolution. Needs to happen.
I'd also love to see some sort of cross-breeding mechanic. Like if you breed two specific pokemon together, you get a completely new pokemon as the hatch result. Hybrids!