Edit - I've made a brand new comparison, which includes THX TruStudio Pro and Razer Surround. Watch it at http://www.youtube.com/watch?v=04yEtZ...
A comparison of the two main 3D audio virtualization technologies for headphones in Crysis 2. Recorded using Sound Blaster X-fi Titanium and Asus Xonar DX cards. As noted, you HAVE to use headphones (it won't work with regular speakers) and you have to disable any 3D audio virtualization your sound card may be using (ie. turn off CMSS or DH while watching the video), otherwise it'll just sound horrible and you won't be able to hear the original effects.