[maw]

Good question. No solid answers here, but my guess would be some combination of more redundancy, better and more active lawyers, and the large players not talking about it when it does go down.

[epoxyhockey]

FB, Google, etc all provide a nice procedure for LEO to query all desired info. It is not necessary to seize equipment. Example: https://www.eff.org/files/filenode/social_network/Facebook20... (pdf)