Great, approved by 2/3 mods.
So if anybody wants to actively help out, these are the tags that I could find:
David, first: thanks for heading to meta to ask this questions! I'd like to think I sort of helped prompt it since I rejected some of your tag edits. Sorry! :/
I think that we really need to settle on tags used to indicate versions, and then migrate the deemed old tags as appropriate. I'm not sure if there is a way for anyone (maybe mod only) to retag all ...
I've done my share on a few tags. I have also removed the tags from closed questions because if you are tagging your question and type "magento2-" you still see them appearing in the suggestions with a >0 count.
Only magento2-dev-beta is still left with a large number of questions.
magento2-pre-alpha > 0 questions
magento2-alpha > 0 questions
I've noticed a lot of users making these 'edits'. I agree with Tim that it's better to be precise in specifying the version but as for the moment the magento-1.7 tag is user 3 times more than the ce-18.104.22.168 tag.
Instead of phasing out either one of the tags perhaps the best thing would be to 'improve' the edit by adding them both when a users requests to ...