While it's preferable to have one final answer, there's nothing wrong in having a progressive answer - the number of edits, however, will bump up the post to the front page - you might have to deal with the voting consequences (few people might consider downvoting your post because it's incomplete).

The other problem is beyond 11 edits, the post will become an auto Community Wiki - this, however, shouldn't be a problem - you can flag for CW reversal. 

On the top of my head, [Journeyman Geek][1] had a similar [progressive question/answer][2] running from [Oct'11 to Feb'12][3].


  [1]: http://superuser.com/users/10165/journeyman-geek
  [2]: http://superuser.com/questions/342107/getting-macro-keys-from-a-razer-blackwidow-to-work-on-linux
  [3]: http://superuser.com/posts/342107/revisions