Not trying to be a wet blanket, but there's nothing really groundbreaking in this talk. It's pretty basic stuff that everyone else running L3 networks already does.
I'd be much more interested in a talk that is solely on proxygen.
I'd also like to know their fragmentation rate is between the L4 and L7 LB's. I know what ours is, but I'm sure FB takes a lot more large uploads than we do. Fragmentation is the downside to using IPVS in a L3 network.
Not sure if the talk covered it, but the core Proxygen framework is opensource: https://github.com/facebook/proxygen