In the last weeks I didn't get too much progress with ShareIt!, between exams and my new job, but specially due to the fact that with the problems I had with the removal of the anonimous XMPP server I was using and that the browsers starting with Chrome v26 generated a big SDP strings, I got fixed on using Chrome v25 if I wanted to keep experimenting :-(
But, in my new job I'm working with WebRTC all the time :-) And doing some experiments not only found that the big SDP strings was a bug of Chrome but also thanks to it another bug on Firefox has been found, but not only that, I was able to find a solution to create smaller SDP strings... and got ShareIt! working directly with Chrome v30 and their native reliable DataChannels :-D Only thing is that seems reliable support is not finished so I'm only able to get fileslist but not files content, so while it got fixed I decided to test it on Firefox and after some work... now it working there.
Yes, ShareIt! working on Chrome and Firefox!!! :-D
Well, sort of. As I said, it's mainly experimental only allowing to get files list, but they are working using native DataChannels, that's a big advance. Now I'll try to be able to use DeviceStorage API on Firefox until interoperability appear since the Filesystem API is not available nor support to upload folders, and also the input tag seems it's a dead end also in Chrome, and maybe I'll start with the Node.js based implementation ;-)