Well, if you're going to nitpick "integrated graphics card" vs. "integrated graphics processor" be ready to have other people nitpick your stuff too :P.
On topic though, as has been mentioned, onboard sound is just fine. When I ran off an Athlon 64 X2 chip for WoW, my X-Fi Xtreme Gamer card was far beyond onboard sound... but when I moved to more modern hardware the difference vanished. I imagine even in the high end a majority of the difference is a placebo effect or even distortion when it comes down to it, but I'm sure if I actually heard a high end setup I could tell the difference. As it is, I don't work with audio high-quality enough for it to matter, and I imagine most people are in the same boat as I am.