A colleague of fine was mentioning recently that it's "hard to keep contacts separate (work/friends/family)" on all the different social networking sites. I couldn't agree more. This is made additionally hard by the fact that each "social network" site imposes their own "classification" of friends. These classifications are not mine and I have to morph my view of my contacts into these imposed rigors.
I would much prefer to be able to manage my contact classifications as "tags". Taxonomies force me into specifying that a contact can be in only one group. I have work colleagues that are also friends. If I could "tag" all my contacts with my own classification scheme and then use that when interacting with social networking sites, life would be much simpler.
I guess this is the "promise" of the "Open Social Web".