I'm going to have to be a nay-sayer and say now I can see why this feature wasn't available previously, and a name change had to be something you spoke to Phil about: already since this has been implemented, I've noticed some members have changed their handles a number of times, and admittedly, it does get confusing after a while in trying to remember who's who when names are changed so frequently - despite there being the username histories and all. I haven't been keeping count, but wasn't there supposed to be limits on how many times members could change their names and how often?
I'm not saying that we need to take this feature away after it's been implemented (though, then again, it was nice that we finally had been allowed to post images in our signatures, but that rolled back almost immediately after it happened), but it does feel like already it's kind of being abused.