Amazon adds static IP addresses to EC2 »

This is great news: Amazon EC2 now lets you reserve static IP addresses, and allocate them to your instances. Previously, IP addresses were dynamic — if you shutdown an instance, or it crashed, the IP that it had was lost: it would go back into the general allocation pool.

This makes EC2 much more viable for running public web sites, because now you can set up a load balancer on a static IP, and not have to worry about dynamic DNS, and clients that ignore TTLs.