1. It is really, really awesome! And there's a lot to do!
Like, vast. And it gets really crowded, really quickly. Going to something like a panel, or a big signing, or even trying to get to the Marvel booth, is a time commitment. I can understand the people that gave up hours to stand in a line (seriously - and it isn't like the lines are absent of entertainment), but we chose to keep wandering instead. There are whole swathes of NYCC that went completely unvisited by us.
We scraped the surface of the iceberg. And what amazed me was how so much of it was free - demos, panels, signings, conversations, shmoozing, browsing, previews, whatever. Some of the best fun we had was in the spontaneous stuff: getting our photos taken for Greendale Community College IDs, for example. The con isn't cheap, by any means, but it is (theoretically) possible to entertain yourself on a budget once you get inside.