What are your thoughts on this...
We were ranked in the top 10 on google for all our chosen search terms.
Last week for no apparent reason we dropped to the 6th page.
After looking round for a reason we discovered that we had probably been penalised for something.
What we think we had been penalised for is in fact CSS hiding text on a page. Now this is entirely for legitimate reasons (displaying text instead of images should someone choose to turn of the styles etc) but it seems google cannot tell the difference between CSS hiding text for legit reasons and hiding text for keyword spamming.
This blog has quite a lot about it (the guy works for google)
http://www.mattcutts.com/blog/
What are other peoples thoughts on the fact that google appears to have a bug that is hindering accessible design?