Try playing with WebSockets, they're pretty easy to get going. Is there something about them keeping you away? Or would it require quite a re-architecture?
There's a lack of browser support (IE10+, no Android), and the fallbacks drain your mobile battery. It's just not quite there. I've done full presentations on WebSockets and toyed/demoed with it for a number of trivial and less than trivial applications, so I would like to think I'm more informed than most.