With BPEL4WS entering a new and possibly explosive phase with the move to OASIS, now is the good time for you to learn a few facts about BPEL4WS.  Check out "On BPEL4WS 1.1" by Collaxa.  Thanks to Edwin Khodabakchian, CEO of Collaxa, for the tip.

Update: the paper was taken down for a day but came back looking prettier.  Go check it out.