Comment 4 for bug 987373

Matt, Maris,
  The ami ids that you are after are probably named "ubuntu-precise-12.04-i386-server-20120424".
  ami-12c77713 ap-northeast-1
  ami-88ca8dda ap-southeast-1
  ami-25e8d351 eu-west-1
  ami-b89842d1 us-east-1
  ami-d5712a90 us-west-1
  ami-cc870bfc us-west-2
  ami-9cd80681 sa-east-1

I'm fairly sure that try.cloud.ubuntu.com is using i386 instances and running m1.small instance sizes. A few months ago, amazon started allowing users to run amd64 images on m1.small. Since amd64 is basically a strict superset of functionality, we may want to start using that.

I'd definitely suggest some test before switching, but basically, I would think that to use amd64 images, you could simply just use 'ubuntu-precise-12.04-amd64-server-20120424':

 ami-2cc7772d ap-northeast-1
 ami-a0ca8df2 ap-southeast-1
 ami-1de8d369 eu-west-1
 ami-3c994355 us-east-1
 ami-e7712aa2 us-west-1
 ami-38800c08 us-west-2
 ami-96d8068b sa-east-1

I've also just realized that you need to update the AMI-ids for hte oneiric images that are being launched, to address the pending move to S3 mirrors (and fixing apt http pipelining : https://lists.ubuntu.com/archives/ubuntu-cloud/2012-April/000752.html )