If it ever comes back, I'd be surprised to be honest. The console makers have been doing fine promoting their own products as they see fit without the expense of setting up a physical space at a trade show. I'd say larger developers are in a similar situation.

Smaller and up-and-coming developers are probably the ones who lose the most out of this being cancelled. Unfortunately, without the bigger names committing, and thus drawing interest, it probably wasn't looking worthwhile.