I’ve submitted the 1.1.0 AMI to the AWS marketplace team for review today, but due to all the AMI updates they have to do due to shellshock it may take up to several weeks for them to process the request.
If you are eager to deploy an 1.1.0 instance, you may try launching it from community AMIs by its id: ami-f4338f9c
Remember that existing 1.0.x instances can be updated to 1.1.0 by using the usual “add system image” command (choose the amd64 image).