Looks good - if this was out 'n around when I bought my X-Fi Music card, I'd seriously consider this. However, since I don't have a receiver with a digital input(actually, no receiver whatsoever) nor do I have a speaker setup beyond a 5.1 Logitech X530, I think the X-Fi still beats it - the Crystallizer whatevers actually do make music and general audio sound better, and it just has more software support going for it in terms of bundled apps, games and 3rd party apps. If you do have such a receiver, the card looks pretty solid, though the woot price could be better. *cough*
For those that do care about EAX, the HDA does EAX via software ("The Auzentech HDA X-Plosion supports A3D 1.0, EAX 1.0 & 2.0 (via Sensaura software emulation", ExtremeOverclocking Review), which will hurt game performance when trying to use EAX. As for the ExtremeOverclocking review itself, I read it as being hugely biased with the writer having some sort of grudge against Creative. As such, I don't really trust any of his subjective comments whatsoever, and I suggest you read the review for the facts instead when making a decision.