The new ElastiCache regions are in Northern California (US West), Dublin (EU West), Singapore and Tokyo (both in Asia Pacific). This means that customers in those regions can add distributed in-memory caching to their applications. The CloudFront/Route 53 additions are in South Bend, Indiana; San Jose, California and a second location in New York. What, still no Texas?
How does Amazon decide where to fire up new services? Amazon's Jeff Barr writes that it's primarily driven by performance and cost. "We also measure latency from various points around the globe to our existing set of locations. We correlate the latency metrics with predictions for growth in broadband Internet penetration and match this up against existing CloudFront usage in the area...We look at traffic to our existing locations and see if some of it could be served up from a different location with better results."
After all that's gathered, Amazon evaluates and prioritizes the locations then starts setting up service in those regions.
Since CloudFront is a content delivery network (CDN), the locations matter quite a bit. As you can see from the global infrastructure map, the CloudFront/Route 53 locations are spread out a bit farther than the AWS regions. Any bets on the locations in 2012?