Another list of BPM Twitterers. If you tweet about BPM, you should join this Twibe; if you follow BPM, check here for any people that you're not already following, or follow the BPM-related conversation directly on this page.
J-C Dichant, who blogs about BPM in French, has started a directory of people and companies who tweet about BPM. If you tweet in BPM, get over there and add a comment, and he'll add you to the list. If you want to follow J-C and don't speak French, use Google Reader and tell it to auto-translate that feed, works like a charm.