It doesn't help within Livejournal, but without — when searching through gmail, for instance. Nor will it help if people change the subject-line with each reply. Also, it will help if ever I leave LJ or if LJ bites the dust.

To tell you the truth, if I miss the old days of usenet; if I were running LJ, the subject line of a reply would, by default, say, "Re: [whatever the original post's subject was]."

Still, if it wasn't clear initially, blank subject-lines aren't that important to me, but more of a pet-peeve.