petehall - 7:11 pm on Jul 27, 2012 (gmt 0)
In my opinion bounce metrics are definitely used, and have been for years. I have seen countless websites rise to the first page only to fall a month or so later because they don't really offer what they claim they do.
Just because you optimise for it, doesn't mean you deserve it... the users tell G this. All IMO of course ;)