johnblack - 7:03 pm on Jan 2, 2012 (gmt 0)
Apologies I should have mentioned my site has disappeared from the SERPS for its usual keywords.
The site is still indexed according to WMT and the 'site' command, still ranks for its domain name i.e. www.example.com ranks for 'example', plus it ranks very low down (50th to 70th) for a small number of long tail keywords, yet has disappeared off the radar (out of the top 100) for keywords it used to rank in the top 10 for.
All this happened on the 25th.
I also checked other SE stats for the same time period
Bing down 30%
Yahoo down 9%
But both showed a significant drop on the 25th which is slowly creeping back up. Google has flatlined since the 25th.