http://www.searchenginejournal.com/google-caffeine-going-live/14596/

<<Thank you!

We appreciate all the feedback from people who searched on our Caffeine sandbox.

Based on the success we’ve seen, we believe Caffeine is ready for a larger audience. Soon we will activate Caffeine more widely, beginning with one data center. This sandbox is no longer necessary and has been retired, but we appreciate the testing and positive input that webmasters and publishers have given.>>

Expect Caffeine after the holidays
<<I know that webmasters can get anxious around this time of year, so I wanted to reassure site owners that the full Caffeine roll out will happen after the holidays.>>
http://www.mattcutts.com/blog/google-caffeine-update/