While going through the tags I noticed "winter" and "winter13". I think that most will agree winter is not specific enough, and could be merged with winter13, but maybe we should look at this a bit wider.
In a short term, release names such as summer12, winter13 can be useful, but do we want them as tags ?
My opinion: As our content grows, and we progress in time, references to the release names will devaluate, and mean less and less to those browsing our questions & answers.
Who still knows what got added in spring10 or summer08 ? Yet I do think, with the fast release schedule of salesforce, and changes happening, some reference should be set to each question. Correct answers right now may no longer be valid with a future release, maybe not now, but possible in a year from now. As releases will stack up, the only reference future users will have is the stackexchange based "question posted Y-m-d ago", which is not enough. I would like to suggest we discuss encouraging the introduction of api-25, api-26, etc tags, and using them on every question.
I consider this the most correct way of naming releases, and it is also how they are referenced to in the sf documentation, does this look like a good approach ?