I got the BOGO email and registered. Did a stay, and got the stay 3 get one free email also. So I just called, they said I was registered for BOGO, not B3GO, and within 2-3 weeks I would get an email wth my BOGO cert or whatever they are sending. She said BOGO was for inactive members ( me) and was "part and parcel" of B3GO.. I think I made a confused grunting sound at that and she said it was one or the other, not both, so if I B another 3 I dont get a GO.
So I would not fret too much over the B3GO email if you did get the invite for BOGO and registered.
And then you can get an extra 250 points after your stay by reviewing the property at bwfeedback.com ^