Thanks for the feedback guys, when we had the sites in beta with the first iteration of the ticket system everyone hated the sidebar :P
I hated the sidebar on the beta because it had useless content, not because it was a sidebar.
It didn't have modification options for the issue you were currently viewing, like suggsted here, or like the one on old-wowace had (or how GitHub does it, or or or), instead it had navigation/filtering for the overall issue list, which is totally pointless to have when I'm viewing a specific single issue right now. It was misleading at best since using it on a single issue view would bring you back to the issue list.
But I gave that feedback on the beta too, several times. :)
I like the tags at the bottom. Its typical for me to also change the tags when I comment on an issue, so having them on the top would require quite a bit of scrolling - especially when there is a lot of comments already.
In fact, the majority of the time I would end up reading at the bottom of a ticket, so having controls there as well is better then at the top.