[tokenadult]

I see that Jakob Nielsen's venerable "Top 10 Mistakes in Web Design" checklist

http://www.nngroup.com/articles/top-10-mistakes-web-design/

just got new styling the other day, as I work on updating my seventeen-year-old personal website.

There are still a LOT of websites that make several of those top ten mistakes. They are higher priority than many of the other issues mentioned on the checklist kindly submitted here. As other comments here have pointed out, it's desirable in a checklist to establish priorities.

[benjoffe]

No. 5 on that list is not valid any longer, fixed font sizes were only an issue with IE6 where fonts specified in pixels wouldn't respond to the user's font size setting.

[halfninety]

Nice list, but I think it can be condensed into one:

Use your own site and make sure you don't hate it yourself.

[onlyup]

Simple but effective advice.