The Steam Users' Forums currently offer the following message: "The Steam Forums are temporarily offline for maintenance. Your patience is appreciated." This may be just normal maintenance, but we have also seen an image suggesting they were compromised in some manner, and for a while were directing users to a site offering ways to cheat at games, so this may be what Valve is in the process of cleaning up. We'll pass on posting the screenshot to avoid advertising the site, and are waiting to see if Valve has a response to our questions about this (it's still early on the west coast). Thanks Joao.