Some weeks ago I asked this big-list question. It was converted into community wiki only 6 minutes later, without giving any notification or comment. Frankly speaking, I wasn't too enthusiastic about that. Of course, corrections to my question are always welcome, but I wanted it still to be my question, without the community wiki label inviting others to freely change the content.
Searching the discussions on Meta, I found out that it seems to be some kind of a convention to make big-list questions community wiki.
Yesterday, a new big-list question of quite similar nature was posted. But it wasn't made community wiki. What's the difference here?
Edit: Now the second question is community wiki, too.