I just upgraded from 1.10.x to 1.11.0rc1 because I had issues with HTML in my web frontend.
I noticed, that an agent doesn't get an email, if a ticket is updated, which works in 1.10.x without any issues.
Just to let you know ...
1.11rc1 is very buggy. Thats why it is not a stable release. Chances are it has already been fixed and when rc2 is released people will have access to the fixes.
Thanks for the update.