So it appears something on Valve's end went awry and many, many, people are having problems playing Steam-enabled games today. No fix has been found yet, I guess we just have to wait for Valve to correct it. Here's a link to the long thread on the Steam forums:
http://forums.steampowered.com/forums/showthread.php?t=492619
The forums are extremely slow, probably from all the people logging in to bitch about this problem.
http://forums.steampowered.com/forums/showthread.php?t=492619
The forums are extremely slow, probably from all the people logging in to bitch about this problem.