I've noticed a recent uptrend in the #3 usage, and like you I didn't note the insulting usage until a few .. well no, perhaps a few months, two or three? I'm faintly disturbed. Anti-intellectualism is never fun, but I also don't think it's useful in any way to water down acafen to mean 'anyone who does met' - fen have been doing meta for ever, way before fan studies existed, doh. Plus it tends to suggest implicitly (if used in an insulting/pejorative manner) that TruFen don't meta; that maybe squee is the only valid fannish response? I dunno. It seems... vague, silly, and toxic, as word usages go.