This happened to me last week, I'd also been having t'interweb issues generally but even when I could see other sites I had the mysql and the db return.
Hang on, I posted on Steam about this so can find out the time (for me at least!)...
3 June 2011, 2233 BST, so that's 2133 GMT/Zulu/UTC, and after a few rounds of Bad Company 2 I'd posted it was up at 0011 BST, 2311 GMT/Etc./Etc.
Please don't disappear again, you've suckered me in to your subsim bosom and I like it here
