[hardwaresofton]

Yep! It's one of the things Ember is (or should be) best known for. The whole "don't break the web" tirade.

React-router should be able to handle it (you said you were using react, wasn't sure if it was in conjunction with react-router), but the documentation that describes the updating patterns of the URL isn't so easy to find... This might help though:

https://github.com/rackt/react-router/issues/266 (Issue from someone trying to change URL without triggering re-route, might help with saving params to URL).

I was thinking that rather than how multitwitch does it (which is multitwitch.tv/<stream1>/<stream2> or something like that), you might want to pass the streams as query string params (ex. "&1=<stream1>").... But then again, you could just use their style. Also it might be smart to selected layout type.