Create new topic without to enter in a forum
It was as Answer Yahoo when you choose the section where create new topic
http://mods.mybb.com/view/create-new-thr...-the-index and they seem to be using a modification of that.
But you want to first populate the topic field on the index and then choose the forum. This brings extra complexity as you now have to find a way to populate the new thread topic field with that variable (the subject field you entered on index). If you also want to fill in the text first then you now have two variables and you are effectively building a quick reply interface on the index.
If you go with FIRST select forum then it is easy to send the visitor to the New Thread input for that forum. It is the difference between adding a plugin and sanitizing lots of stuff, or just using the existing MyBB tools.
We can't copy "showthread new thread" and to add list of all forums near to it?
Anyway if it is too hard etc then better as you say, that is users are redirects to forum section?