Should security summits be secret?

Just finished reading Kelly Jackson Higgins report in Dark Reading on the "secret" security summit hosted by Microsoft.  Once I got over the humiliation of not being invited ;-)  I spent some time thinking about it.  Is it a good thing?  Yes, I think it is.  I think it is important that the relevant parties get together and talk about what we can do for the good guys to win the Internet security battle.  As the article says, there is no substitute for in person meetings, even in the digital world and all of the virtual meeting technology available.  What will come of this meeting?  Who knows.  As the article says, even just the potential networking would probably be a good thing.  The biz dev person in me says that is certainly the case. 

The problem I have with it, is why all the big secrecy. Instead of being a summit like the Yalta meeting of the WWII allies trying to beat the bad guys of their day, it seems more like a mafia chieftains meeting in Appalachian or something.  Visions of Bill Gates, John Chambers, Steve Northcutt and the rest being led out in cuffs after being discovered by the local sheriffs. Why the secrecy?  Were they afraid of infiltrators? terrorists? what?