Ask HN: What's are the key differences between Pusher and PubNub?
I know Pusher supports WebSockets and at one point PubNub did not. What are the salient details you used to choose one over the other?
-Pusher sells itself as a WebSockets platform, whereas PubNub is a protocol-independant: it uses the best protocol and technique based on the environment you're using. That means you're protected from dealing with newer protocols on older devices. As techniques mature, PubNub gradually incorporates them into its architecture.
-PubNub is globally distributed in 10 data centers. Pusher is not.
-PubNub's performance is better than Pusher's, according to at least one customer. (https://twitter.com/thfriendly/status/220152602917220352) PubNub's codebase is as close to the metal as possible: written in C and with lots of kernel modifications.
-If you visit Pusher's website and click on the "Scalable" tab, it lists: "40 billion messages delivered". In June 2012 alone, PubNub delivered 44.2 billion messages.
-PubNub recently hit a peak of 1,000,000 messages per second. (http://techcrunch.com/2012/06/13/pubnub-pulse/) I'm not sure on this one, but I don't belive Pusher's numbers are anywhere near that.