Yeah I don't use the AWS much, how does this different from GAE? Hasn't GAE existed for a while already? I feel like it's always had it's uses, and it's very nice! But the revolution didn't happen five years ago, don't see why it would happen now.
The difference is that Lambda is a) way more annoying to use, b) gets way more coverage, because developers are locked into the AWS ecosystem and often don't pay the bills.