Mark Pilgrim has upgraded his site to valid XHTML 1.1, and in the process provides several examples of why that's really quite a bad idea. I shall stick with my grossly invalid approximation of HTML4.
In addition, he starts the push to the second stage of reducing weblog bandwidth costs, mod_gzip. I considered mentioning this back during the Get thing, and it was suggested to me several times that I should have, but one axiom I've learned is: “Make one suggestion at a time, or you'll confuse people.”
.