At the request of authors, publishers and Google, the court has extended the deadline to file for an upfront payment in the Google Book Settlement. Any author or publisher claiming an upfront payment -- a "Cash Payment" -- will now have until one year after the Court's final approval of the settlement to file.
Authors whose works were scanned by Google on or before May 5, 2009 may be entitled to claim a Cash Payment. If you are not claiming a Cash Payment, you may file at any time.
The deadline to remove your work from all databases (we don't recommend this, since it may be irrevocable -- you'll have more flexibility by simply blocking displays) is still April 5, 2011.
Find out whether your work was scanned, and read the filing instructions here: Google Book Search Claims
Final approval of the Google Book Settlement is still pending.