1. Legibility Problems
2. Non-Standard Links
4. Content That's Not Written for the Web
5. Bad Search
6. Browser Incompatibility
7. Cumbersome Forms
8. No Contact Information or Other Company Info
9. Frozen Layouts with Fixed Page Widths
10. Inadequate Photo Enlargement
Santa has come early this year. Most of these are repeats; I guess it's safe to assume that the vast majority of web development is a wee bit stale (or according to Nielsen needs to get "back to basics")? I have to cop to a couple of these (fixed-width, anyone?), but we all know Nielsen's just a stickler for his rules.
A good read with some good links, nonetheless.