The threads are pinned up not just for the importance but also for easier access to the members.

The mode of selection are as follows.

1. The uniqueness
2. Good contribution
3. Important
4. How often it is getting updated despite the above 3 modes of selection. for eg. some threads are good and with good content but do not get updated often depending on the poster and participation. Such threads get lost in the background when new threads and posts keep appearing. Such threads will be pinned so as to enable the user to locate them.
5. The pinned up threads will be changing over a period of time, so as to accommodate new good ones.

Thanks,
Cheers
N
ps: This is a trial attempt and will be modified shortly.

The idea behind pinning is to basically organize some well presented threads which tend to be lost in the several threads. If you have any objections to it, I will undo the whole process.

cheers,
N