BillyS - 12:06 pm on May 9, 2010 (gmt 0)
cien - You can do that in Google's Webmaster Tools, but it will take months to come back. This is what Google says, but I've no experience with an entire site. I wouldn't do it if I were you. I'd wait for Google to fix it through their "normal" process.
How to remove all the pages from G's index and have them reindex the site?
Content removed with this tool will be excluded from the Google index for a minimum of 90 days. You can use the URL removal request tool to reinclude your content at any time during the 90-day period.