In How should we document version tags like Tridion-2011 we decided to use just product version numbers such as 2011 or 5.3 for tags related to specific versions of a Tridion product.
At the time we didn't explicitly discuss whether we wanted to have tags for specific service packs or hot fix rollups although I think it was implicit in Nuno's answer we would just tag them with the major version number of the product.
Recently we've had three questions tagged with 5.2sp1. My inclination is they should be retagged as 5.2 but I wanted to see what everyone else thinks first.
What should the tag convention be for questions mentioning specific service packs or hotfix rollups?