Tekken has always been a fan service game. TTT2 continues giving the fans everything they want. I could do without the bikinis and whatnot. But, it will likely be the most stacked and packed fighting game of all-time. Much like Tekken 6, TTT2 gives fans limitless possibilities for customizing every character. I also like that TTT2 lets you fight solo or tag team style; that's something I think SFxT and the MvC series missed the boat on. The achievements are also good and fair; nothing ridiculous like in Capcom or MK9.
I'm not exactly sure what Tekken Tunes has to offer that we don't already have. You can already replace the in-game music with your own music for just about any game on the 360, including Tekken 6. In fact, I created a custom KMFDM soundtrack to use whenever I play T6. So, outside of a few easy achievements, I just don't understand what Tekken Tunes offers that is new.
In any event, I pre-ordered it months ago, and can't wait to play it. T6 and MKAK are the only games I have completed 100%. From the looks of the achievements, I can complete TTT2 100% as well.