When I was upgrading hugin today, I saw the following:

 [...]
 Trigger für menu (2.1.47) werden verarbeitet ...
 Trigger für shared-mime-info (1.3-1) werden verarbeitet ...
 Unknown media type in type 'all/all'
 Unknown media type in type 'all/allfiles'
 Unknown media type in type 'uri/mms'
 Unknown media type in type 'uri/mmst'
 Unknown media type in type 'uri/mmsu'
 Unknown media type in type 'uri/pnm'
 Unknown media type in type 'uri/rtspt'
 Unknown media type in type 'uri/rtspu'

 [at this point the process stalled, no further progress]

A CTRL-C interrupted the stall and let the installation continue.

This is actually not the first time I am seeing this. This has allready
happened in the past.

It looks somewhat similar to #739252, that was reported one year ago,
without any comment of yours.

Sebastian, are you actually still maintaining this (or your other
Debian) package(s)? If not then please orphan it, so hopefully some
else can take care of the package.

The reason I am asking, is that #663439, open since 2012, without any
reaction of yours, seems to be a duplicate of #772538, encountered by
at least two people, open since last december, also without any
comment of yours, and the latter even includes a hint to a solution
of the problem.

I'm not sure why there are not more "me too"s in the bug reports,
however if this stall is encountered by other users, especially not expert
ones, then it might well prevent them from properly upgrading to jessie
and leave their system in a weird state.

Sebastian, please take care of the bug reports against shared-mime-info.
Don't let bugs get into the way of a clean wheezy-jessie upgrade experience.
*t