Sadly, according to PhoneArena (link below), the Wolfson DAC has been replaced with a Yamaha-branded one. I'm not certain as to what model it is, though I'm hoping that the performance is at least as good as on the original Galaxy S' DAC. It wouldn't make sense for them to lower the quality of the Audio Output, after all, would it?
http://www.phonearena.com/reviews/Samsung-Galaxy-S-II-Review_id2728/page/4