They're going from 2+MB (for some reason) to 300KB - even if decompression is "slow," that's going to be a win for their bandwidth costs and for perceived speed for _most_ users.

I was surprised to see little server-side CPU benchmarking too, though. While I'd expect overall client timing for (transfer + decompress) to be improved dramatically unless the user was on a ridiculously fast network connection, I can't imagine server load not being affected in a meaningful way.