www2.sandbox.google.com which was supposed to be caffeine's test platform is no longer valid, on opening we get the following message from Google :
Cool, so i guess we can expect the integration of caffeine soon.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.