brinked - 8:50 pm on Mar 15, 2010 (gmt 0)
WN, I have been lurking these forums. I never really posted because at the time it was better for me to listen rather than inform.
Right now caffeine has been lifted from everywhere I can see...which is pretty normal, they will probably pop back later.
Why caffeine can be found in some cities and not others is interesting. It could be that google just decided to test in cities with predictable search habits. Cities like new york and California are areas where a lot of technical people are, a lot of SEO companies, tech firms etc. Google does not want to test caffeine on people like us, they want to test caffeine on what they consider to be the average searcher.
Google has a lot of information they use when deciding where they should test caffeine, we will never know the true reason because I highly doubt they would make this decision based on one or two factors alone.