Unlocking the upvote privilege

After thinking about this for some time, I would like to see user’s reputation breakdown by site and each tag they’ve participated in, so I could have a better idea about this “obviously very high rep user, but do they really know much about C# or are they mostly an expert in PHP or something else”.

Just the gold tag badges like on SE is a very vague source of that information, and isn’t really as useful as it could be.