They are much more ubiquitous than the terminals. But
they are very
heavy. Typewriters in general are becoming less common, but I suspect
it will be some time before Selectrics start becoming scarce due to
the number produced.
Selectrics are also still in use in more than a few small offices.
Additionally, there is a small (but larger than one might expect)
group of folks that collect typewriters.
--
Will