Unless it changed within the last 10 minutes or so, you can only PMP on thread creation. You can't edit an already created thread and promote it later. I feel like this was a mistake on Gaia's part. I highly doubt people are going to recreate their large threads to use PMP.
Also, I still have questions about PMP, and it seems like they're not answered anywhere.
- How long does it last? Is it permanent?
- Does it keep threads on the first page (so you don't have to bump them anymore)?
- Will there ever be more than 3 colors?
- Can you ever un-promote your post at will?
Also I feel like 100GC is a little steep. Unless it's permanent, I suppose. But then you run into a bunch of inactive PMP threads stuck on the first page for however long.
I just don't think this was thought through completely on Gaia's side.
(edit: At current, someone has used PMP in the chatterbox if you'd like to see it in action)