Ironically enough, I was on Dean Edwards' site a couple of nights ago and completely missed this. Dean Edwards' has put together a neat little behavior for IE which attempt to correct IE's support for CSS2, called IE7.
The idea behind this behavior is that you can use IE's ability to dynamically alter a stylesheet in order to correctly display CSS statement currently not support by IE5+. It does this by changing the CSS statements to styles that IE does support and that will mimic the correct CSS behavior as per the W3C spec. This behavior will also attempt to correct a few other issues IE has with compliancy—such as PNG transparency. Make sure to check out his list of compatibility fixes.
It's a pretty cool idea that could help developers start writing W3C compliant code. I've been developing websites professionally since 1995 and always trying to hack code in order for it display correctly has gotten very old. Anyway, go applaud Dean and his affords.