What makes a great security conference?

A friend recently suggested we start up a security conference, and it has got me thinking a lot about security cons in general.
What makes a really good conference?
Is it the presentations? workshops? free stuff? just being able to hang out with other interesting people? (The drinking? ;-))

There are lots of fundamental questions you need to think about from the get-go,
Who is the conference audience?
-Is it general security? Offensive? Defensive?

Very technical? What sort of subjects would you want talks on?
How many people do you want going? (Roughly)
Where area do you want it in?
-City or at least region
How are you going to get the word out to get people excited & want to come?
-blogs? twitter? website? connections? podcasts?
Do you want to make it a free conference? If not, rough cost?
--is free even feasible? Sponsors? Do we have enough money to invest? Favours?
How long do you want the conference to be?
How many presentations do you want?
How are you going to get people to enter the CFP?
I personally feel the best things about a conference comes down to 3 things: 

getting people to come, a good place for people to hang out & get to know each other and great presentations.

I'm really liking the idea and challenge of organising and creating a conference (and all the problems that go with that), but I think there are some fundamental ideas that need to be sorted first.

But perhaps the best thing to do is just try to get on with it and not get too distracted, otherwise it may just get put off indefinitely.

Seeing as I want to know what people like most,
what are the key points that make a conference great to you?

Please leave comments for some suggestions

-lavamunky