BBR is a mod by Siredblood. 34 of us played in STL in Feb. Main game in Atlanta in september. Its different which keeps it fun.
PBEM meant play by email but its a euphemism for an asynchronous game (played 1 turn at a time remotely). Today its PABI (Play asynchronously by internet). You can also seralize a live game the same way (leaving it set up and only playing 1 turn a day or week). The “forum” is that people post the turn here on the internet–you publish your Tripple AAA log to this website and then they load that into their version of Tripple AAA, because its not a modern networked style game like Axis and Allies online.
PBM was when people would play chess by post–setting the board up at both their houses and then sending a note, letter or postcard for each move.