I have all of my code on github under a CRAPL license [1]. It assumes a certain amount of good-faith from others, but I feel that if you're worrying about getting scooped, your problem isn't ambitious enough. Luckily, my adviser agrees, and is very in favor of open releases of data [2].
That will never happen, because the universities are bigger than the journals and will push back. The universities want to own the code if there's money to be made. Stanford made a small fortune from Google, for example. If journals required code review, other journals would pop up that wouldn't require it.
When it happens, I hope that they'll manage to agree on a sensible license (even though I won't set my hopes too high).