Summary: Amazon just announced a new pricing model for reserved instances. At a quick glance, it appears to be better in some scenarios, worse in others. For in

Summary: Amazon just announced a new pricing model for reserved instances. At a quick glance, it appears to be better in some scenarios, worse in others. For instance, the "No Upfront" option gives a 30% to 50% discount from on demand pricing, with no upfront payment -- though you have to commit to using the instance for a full year. On the other hand, a 3-year Light Utilization reservation used to be a great way to get a substantial discount without much upfront obligation, and that doesn't seem to be possible any more. (Though you can still buy Light and Medium Utilization reservations until Feb. 2.)