A major thread on Hacker News today and the tech blogosphere last week.
What looks like one of the largest apps built on cloud services runs on
Postgres- or more exactly pgpool-II. The architecture is worth checking
out:
http://aws.typepad.com/aws/2008/12/running-everything-on-aws-soocialcom.html
It wouldn't be surprising to see Postgres win mindshare over all other db's
on the cloud.