Well only yesterday I asked a question on StackOverflow and noticed that there does not seem a way to monitor a question without answering it. So even now it needs more polish.

Probably after one weekend a clone would not be as polished, but it might be usable enough. If it picks up, there is still enough time to add polish by and by (maybe taking another direction than SO in some respects).

Also if it is open source there is a chance that other people chime in and help adding features they miss.