Disagree. The mantra here is 'apps before libraries'.
If the apps stand by themselves as parts of core, the library
deps stand by themselves. If they don't, the libraries don't.
In essence, apps should be moved because of duplication of
functionality/not required functionality. Not because of toolkit
alone.
Otherwise, you'd get into the situation were "we moved this
out because it used gtk1. Now it's ported to gtk2. Let's move
it back!" Which is just plain weird.
Good points.
-sv