Yes, the Packages(.gz) file (found in the feed) is simply a text file containing the control file contents for each package.
Assuming there are descriptions in the control files then they will be listed here.
Probably not quite what you want, but that's about it (if there's info missing, then patches to the OE metadata might be an idea.)
You can also get info about a given package by doing:
ipkg info <package name>
This ought to work too:
ipkg info *opie*
Si
