Many graphic designers I've met think CSS is a once-yearly conference in Vegas. I consider a "web designer" to be a superset of a graphic designer. They can do everything a traditional GD can, plus break it down into html/css (the cleaner the better).

I value them more highly than the user experience designer, because it's considerably easier to improve the user experience. Focus groups and a/b testing are fairly easy to implement and allow you to make great strides in a short period of time (the latter is obviously not true if you have little traffic though).

I can run an a/b test in far less time than I can make a great looking site.