Just to address the “cons” in jsbin (too :)
If you switch between different versions of the library, then it’ll just swap out the script, though I think you want to switch back and forth really (though it used to exist, I removed it for simplicity).
Yes it is (and has been for over a year now), select “share” and copy/paste the embed code (or just wrap your bin in an iframe and change /edit to /embed).
No way to save to the original bin (or rebase).
I’ve never quite been sure what this is. I’ve heard jsfiddle has this rebase thing, which because I’m not user, I don’t really know what it is.
You can save the original for sure though (but I suspect you mean something else, like restoring).
Other “pros” that I think are pretty big, but missed out:
CodeCasting (also known as Professor Mode in CodePen pro accounts)
Remote rendering (i.e. point any other device, mobile, old crappy browser to the same url, and it’ll live reload as you code)
Locally installable (via npm install jsbin)