All of my reputation from Unix SE just appeared as 'new' to me on my meta profile. I have visited meta before (and it didn't display it all as new before). Is this a bug, or is it intended?
The reputation tab really isn't intended for child metas...as your reputation is from the parent site, but the history of that reputation isn't synced at all.
Given this makes no sense to show, starting with the next build the reputation tab will disappear from child metas.
IIRC there's some kind of obscure bug where the computation leading to that number mixes meta rep and main site rep. Something like computing the main site rep gained since the last time you viewed your rep through the rep tab on the meta site. This may in fact be a feature, because meta rep is not supposed to be added up.