In 32-bit mode you can use the same methods and kexts as you would use in 10.5.x:
Chameleon built-in injection
Injector.kext (NVEnabler is awesome and currently the only way to get analog TV-Out working)
DSDT
Device Properties String
In 64-bit mode:
DSDT
Device Properties String
I think I saw a version of NVInject or Natit compiled for 64-bit Snow but I can't remember where.