I second you on the sollozzo shooting scene - took my breath away. On the subject on Fredo knowing, I kinda thought that he may have thought it was possible he was gonna be killed, but then I thought that, being quite cowardly, Fredo would never have got in the boat if he knew he could be killed. Mmmmm. I guess we'll never know for sure. A bit like Fredo in a way he he.
Ciao!