I've noticed a few threads on the forum that integrate Alfred with JIRA but wasn't quite able to find one that did everything I was looking for so I decided to try my hand at writing my own (in Node.js).
Here are a few of the features:
List issues assigned to you
List issues that you are "watching"
Assign an issue to a user
Transition the status of an issue
Quickly add a comment to an issue
View an issue's priority
Watch/Unwatch an issue
Open issue in a web browser
I'm still in the process of developing the workflow so I haven't yet created an .alfredworkflow file. That said, if you'd like to install and test the workflow for me, instructions can be found on my github page. If you have suggestions/features those are certainly welcome as well.