You decided that Numeric version tags considered ... OK and the
2010 tag exists.
SharePoint has big differences (Feature/Development wise) between the 2007 & 2010 version and one should differentiate via tag IMHO (same goes for a newer version once it comes out).
Right now the "sharepoint2010" and "sharepoint-2010" (same goes for 2007) is blocked. Why not create some synonyms for those instead of blocking them as
2010 is allowed.