I have started to see what to me is a new convention in multi-response blog comments, the use of @ plus a previous commenter’s name to indicate that the current comment is aimed at that person rather than being a response to the original post: for example (to quote one example from Language Log today)
Ryan Rosso said,
July 8, 2008 @ 10:06 am
@jagorev: I would agree
Have I been hit by the recency illusion in thinking this has only just started happening? Does anyone known when it began, and why the @ symbol was chosen, rather than (as would seem more logical to me) saying to: or something similar? (Comments on whether this is an unnecessary and irritating affectation are probably ultra vires ...