I’m currently looking for a high quality webcam to replace my infuriating Logitech Quickcam Express (it works with everything but skype – I have tried *almost* everything but frankly the picture is so lousy maybe it’s not worth bothering anyway!). Anyway, I came across this page:
https://wiki.ubuntu.com/SkypeWebCams
It says which webcams have actually been tested with skype under linux. I might test out how reliable this list is tomorrow…