virtual machines hold great promise as a way to distribute hard to configure applications. i have been using jeos vmbuilder (and some bash scripts) to generate my appliances, but i'm looking for something more elegant.
in my case, i'm looking for a solution that will build a linux-based vm with configured versions of tomcat and mysql as a base. each future release would be a new war file and a sql update script. it'd be really nice if already deployed vms could self-update and test builds could be pushed to ec2.
in my brief search, i've found rpath rbuilder, turnkey linux, vagrant up, suse studio, jeos vmbuilder, and vmware studio. rather than try all of these, i figure i'd ask what this community uses to build and distribute appliances...