As it was expected that Caffeine will slip in search in late 2009, it is now live on one Data Center. Before few days Matt Cutts intimated about the Google caffeine will be live soon . Caffeine will be live on other data centers after the holidays.
Matt Cutts from Google confirmed that Caffeine is live 50% of the time in the 209.85.225.103 data center.
Update from Matt cutts:
My plane landed and I had time to check. 209.85.225.103 as an IP address currently hits the Caffeine data center about 50% of the time, so that’s probably what the person at DP was seeing.
I think it’s really risky to take a few threads and turn that into a “major Google update.” For example, one of the links you pointed to was asking about the rankings for their site webtlk.com. Given links like http://74.125.47.132/search?q=cache:iwkj8P8xoSEJ:teqtonik.com/+http://teqtonik.com/&cd=1&hl=en&ct=clnk&gl=us&client=firefox-a talking about data recovery and pointing to that site, I’m guessing that Google just got better at determining how much weight should be given to links to that site.
So 209.85.225.103 does hit the Caffeine data center more often than other IP addresses, but it’s always been the plan that Caffeine would roll out at one data center (no more data centers will get Caffeine until at least January).
But I would avoid generalizing, at least as going by the one report that mentioned a specific site that I looked into. Of course, on a lot of the webmaster forums you can’t tell what site they’re talking about, so it’s hard to do any debugging on what might have happened to individual sites there.