E3 was for the longest time just an industry show and it did that pretty well there's a lot of interesting stuff that happens just because you have so much of the games industry in the same place. One of my favorites are the couch interviews put on by Giantbomb. They get all sorts of names big and small to come and chat every night. That's the kind of thing a purely digital media strategy can't really replicate.
I was always curious why it matters at all.
As a consumer you have to wait ages and as a journalist you are there a day earlier or have invites.
It's much cheaper to invite all relevant journalist on a global scale.
But honestly? If I'm able to watch the release show from companies like Ms Sony and co live on YouTube I will do that.
I assume this creates more then enough buzz already.