I'm not exactly sure when Valve made them available, but player statistics are now publicly viewable on the web. You can keep tabs on my stats as I make progress on the various achievements recently added for the Medic and Pyro classes. If you click the "Return to jgbCodeMonkey's Steam ID" link, you can view stats for a few other games (though not all games report stats).

In other related news, Valve has recently put up an official Team Fortress 2 Blog. Lots of behind-the-scenes artwork is being shown, and some explanations for decisions they've made are presented. While the blog isn't the most active in the world, the nuggets of information they have provided so far are quite intriguing. Definitely a recommended read for fans of the game.