Sounds like focusing on technology, rather than a clear problem that you have a solution to.

Comet technology (If you want to call it that) is fantastic. I wrote http://www.mibbit.com using the techniques, and you can bet it loads a lot faster than flash/java applet/anything else. Also these days with browsers on far more platforms, you're not guaranteed flash support. (Not to mention it being proprietary/slow/etc)

Focusing on comet though seems like saying "I want to do a web2.0 startup" or "an AJAX startup". They're all just buzzwords with little substance.

Does look like you've got a great system, just need the killer app now :)