I have an ageing Logitech Webcam (messenger plus) with built in mic. this mic. also doesn't work with win7, unless you alter the Vista-version driver a bit.
You can get a Win7 certified webcam for about 10£ with a working microphone - That's probably the easiest way around this issue.
Creative is number 1 in the world when it comes to being lazy about driver updates. My X-fi Soundblaster-driver is more than six months old, not WQHL-certified and doesn't really work with hardware accelerated sound in windows 7.