I posted a question How can I fix EXM 3.3 Upgrade Causing Message View to Fail? on the Sitecore StackExchange and I tried to tag it with exm3.3 and exm-upgrade, but I do not have a high enough rank yet.
I think having exm tags for each version would be good to separate issues for each version of the module.
I think having an exm-upgrade would be good to separate issues with module upgrades such as exm from the main upgrade tag which should be for upgrading Sitecore itself.
Can we add these tags?