Not a fan of personal tags.
Yeah, jury is still out on them. They don't seem to be getting much love or disdain, just "meh". I'd be surprised if they were still present as they currently exist in the rewrite.
I would like to add my voice to the group that thinks tags in general need a sort of overhaul. Should definitely exist, but probably need their own page of settings vis a vis how users can wield them. And I would still love to be able to "rank" the things I follow: individual tags, users, domains etc. I follow a lot of stuff, and while I never want to miss a War Nerd article, I don't need to see everything from #music. I can't imagine others feel too differently.
Okay, but riddle me this: Why do you need to blow a tag to make a personal tag? The fact that you posted it to that tag means that without you doing a thing, I should be able to follow that tag but only if posted by you. That you had to give up a community tag to provide me a benefit that should happen automagically strikes me as a waste.
It's a neat feature to have, I haven't needed it yet, but I can see how they'd be useful. I'm sure I'll follow one eventually.