The "Firefox for devs" link from the front page currently goes to "Firefox 4 for developers". I've created a new "Firefox for developers" page (https://developer.mozilla.org/en/Firefox_for_developers), which I've set to redirect to "Firefox 5 for developers". We can easily update this redirect on the wiki side as Firefox moves forward. So, the link on the front page only needs to be changed once.
qa-verified stage https://developer-stage9.mozilla.org/en-US/
verified fixed https://developer.mozilla.org/en-US/