I was thinking about what you said about not talking about things that happen when you're not together as a group. I don't think it's stupid, but my wife and I have always been about full disclosure.....no secrets. To be honest, I usually quiz the wife about things that went on with us and our playmates but only because it gets me turned on to hear her talking about it. I usually have to bring it up during pillowtalk though. Otherwise, she's still a bit shy to just come out and say, "his cock felt soooo good inside me" without a bit of priming. Talking about it while playing with her is the key for me.
Of course, since you, Bob and Kenneth are talking on the side, there's really no secrets to be had. I would have to think the girls are talking as well. Don't let their shy demeanor fool you. Experience has taught me that women can talk about sex amongst themselves as much as, if not more than, men can. I'm sure they're comparing notes just like you guys are.
I'm glad to see that Bob and Kenneth finally swapped wives. This means that all the guys have been with all the girls and vice versa. For a while there, you and your wife were the only ones that had experienced both couples. I found the guys offer to your wife quite intriguing though and must admit I would have loved to have read about a threesome between your wife and one of the unmarried couples. Just the thought of it is rather hot and exciting.
So will you and your wife have an audience on the boat? I would have to say if you leave the door open, you will most likely be watched

That's just a hunch though. I suppose there's a lot left to tell about this weekend though. Plus, I'm curious to hear what happened, if anything, when Jim's wife came back over to sunbathe.
Looking forward to the next update!