I've been using GitHub for a little more than a month now, and it's been about 2 weeks since I shut down the machine running my local Subversion instance.
GitHub for Windows needs some work, but given that Phil Haack is/was working on the Windows aspect, I feel pretty confident that it'll continue to get better.
Moving to a system that allows for public repositories also allowed me to publish some really old code, that might be of benefit to someone. However, I am now paying $7 a month something that I wasn't before. There is a free Git provider that I've looked at (and that I might use as a backup), but there's a benefit to having everything in one place. And GitHub seems pretty solid in the Git space.
View all my public repositories.