There has been some good testing of the 7.x dev and it should be mostly stable at this point. Will probably leave this in beta until User Relationships itself hits 7.x-1.0, but don't want to discourage people using it in the meantime.

The code and feature set has stabilised and is now in use on a number of sites. If we go a while with no issues reported against this version we'll call it 1.0 and drop the release candidate status.