tedster - 9:19 pm on Feb 2, 2012 (gmt 0)
There were a few reports last year about ranking problems on sites that did extensive title tag changes - especially if it was done more than one time. Your is the first I've seen in recent days however.
Many members here assumed that Google was doing this to obstruct reverse-engineering attempts. in other words, trying to make titles that find the Google sweet spot instead of writing titles for visitors. Still might be the case.