There has been lots of talk of ZeroMQ as a message transport in hook.io, it's coming soon.
IMO, you shouldn't be worried about messages per second between devices right now. You should be worried about how you are going to communicate between 1000s of 3rd party services. hook.io aims to solve that problem.
Listen to this man! We're struggling with the same thing at my startup (https://zapier.com/), and having a robust way to hit some of the crazy API's out there is by far the most difficult thing we've come across.
hook.io supports multi-transport messaging protocols.
There has been lots of talk of ZeroMQ as a message transport in hook.io, it's coming soon.
IMO, you shouldn't be worried about messages per second between devices right now. You should be worried about how you are going to communicate between 1000s of 3rd party services. hook.io aims to solve that problem.