Glad to see Kazuya making it in! Tekken seemed like a long overdue addition for Smash Bros., and while I'm not super familiar with Kazuya (of the four Tekken games that I've played, he's the second-to-last unlockable character in one, and the other three have so many characters that I haven't gotten around to playing as him much), it's great to see him in Smash Bros.
I'm pleased to see that they've added so many villains to this game (I think Kazuya counts as a villain? From what I've seen, a case could be made for him or Heihachi), since that was my biggest complaint about the roster in previous Smash games. In this one alone, we got Ridley, K. Rool, Dark Samus, technically Piranha Plant, Wolf returning, Sephiroth, and now Kazuya, which is a significant boost from when it was just Bowser, Bowser Junior, and Ganondorf. (and Dedede, if you stretch it)
Also, in case anyone missed it, this was posted on Harada's Twitter:
Also, Kazuya's page is up on the Smash websites (no alternate palettes yet; just the two costumes), and this screenshot is great.