Wanted (in collection) / Wishlist
As many of us are indeed collectors, also focusing on collection automation within trakt.tv, people may want to differentiate further between stuff they like to watch (Watchlist) and what they actually like to collect (Wishlist - as seen and implemented in apps such as Movist)
Having a separate smart Wishlist, which is updated automatically as soon as items getting collected, may give us the best of two worlds, in addition reducing the management impact of the given Watchlist especially when it comes to bigger collections.
On a side note: there seems to be a growing number of apps out there able to import watchlists
like the ones from trakt.tv etc. As long as those are more like overloaded multipurpose lists and not true watchlists by definition, importing them somewhere strikes me as making less and less sense. So purifying them, giving them back their very meaning by separating the above purposes may turn out to be helpful on many levels.