Now, usually it's clear from a weblog how much personal information the maintainer is interested in sharing. If someone posts their name obviously on their weblog, I'll list their name in the index on my site. If it takes a few clicks of navigating to some other site they maintain which includes their personal information, I won't usually bother explicitly linking weblog to person in my list. The thing about email, however, is that a great many people use their real names in it, even if they don't use it in their weblog itself.
The hints given in the weblog about which I was most recently informed gave me enough clues that I had a pretty good guess which university the grad student was at - and indeed, the departmental webpage confirms it. As a rule, this information is fairly meaningless to me, but in this case I was briefly tempted to connect the dots, and tell my other contact at this university that a fellow member of their department had also started weblogging. But I've resisted - it seems the tactful thing to do, since neither mentions their own name on their site. They can figure it out themselves, if they can and choose to, from browsing weblogs.