Valve did make an official statement to the press on the day of[0].
[0] http://www.pcgamer.com/warning-steam-is-revealing-private-ac...
Call it petty, but hearing their official statement secondhand makes it feel disingenuous to me. They have more appropriate channels in place for that sort of thing, including email, their two official Twitter accounts, and their very own web site, which would communicate directly to the customers affected.
To quote a NeoGAF moderator:
> To be honest, I think people would have been willing to give them 5 days (irrespective of what the professionally appropriate timeframe was) if their initial response wasn't so tone-deaf.