Just the promised follow up to those that are interested.
Sort story.
It's as simple as getting the right soundcard. As long as it supports Dolby Live/DTS Connect. Either of these technologies will work.
Dolby Live DTS Connect
What they do is convert the audio files in games into a Dolby/DTS signal that can pass 5.1/7.1 through an optical or other SPDIF output. Something your receiver will be able to decode.
I had one person confirm that he uses Vista and a soundcard with Dolby Live and has no issues.
As far as what Vista supports I don't think that question will actually be fully answered.

There seems to be some debate if it supports EAX5 or just parts of EAX. Also, someone mentioned that only Vista supports DTS connect. Either way, the conclusion to that is it's a non-issue as a card with Dolby Live should work with any Windows OS. Some games use EAX and the more current games also have Open AL which seems to be what most games are moving to. Worst case scenario older games may not get converted to 5.1.
So, any X-fi card will work. Even ones without the Dolby Live option can get upgraded with a $5.00 download from Creative.
http://buy.soundblaster.com/_creativ...DDN6Z2H2ADDEZD
Also cards with C-Media CMI8788 will support Dolby Live.
That pretty much leaves a few options from Creative, AuzenTech, and HT Omega as well as a couple others. I'm still leaning towards HT Omega, but my budget may make me go for something else.
So, yay for me.
