I just wanted to add to this that I am very happy with Deluge 2.2.0 + libtorrent 1.2.19. Some quirks I experienced, most notably a portion of torrents coming up as paused on restart in 2.1.x seem to be resolved. and console seems to perform better.
As for libtorrent 2.0.latest, I sticking with 1.2.19 for now, if it isn't broke, don't fix it.
Libtorrent 2.0.8 update.
Re: Libtorrent 2.0.8 update.
This is why I recommend 1.2.x for everyone, qbit, deluge, whichever your taste - 1.2.x just performs and manages things better IMO.
Deluge

