Sonic Colors was a massive success how? I doubt it did much in terms of sales, but it's also a kids' game and the core audience for the 360 and PS3 is adults, so porting it to them wouldn't have proved lucrative. TvC is a shitty button-masher and it doesn't have the name recognition that games like MvC and MK have, so this is why it was a Wii exclusive. Sucker Punch only makes games for Sony systems, so I'm assuming they're not licensed to make 360 games.
A lot of PS2 games weren't ported to the original XBox because the original XBox wasn't nearly the success that the PS2 was. They stopped selling new XBoxes in 2006 and they STILL SELL new PS2s. The PS2 has had almost twice the lifespan of its biggest competition and is even now the highest selling console in history, so to compare this issue to that one is ignorant as shit. The 360 is the dominant system (compared to the PS3 and in terms of sales), and that's why it would be foolish to give exclusivity rights to the PS3.
But none of this matters anyhow since the HDK isn't happening, so this whole discussion is pointless.