I recently added a new tool called 'ptomorph' to Panotools::Script
that helps with stitching Hugin panoramas with parallax errors.  To
give an idea of what it does, here is a 'before and after' example
of a handheld panorama with quite a lot of stitching errors:
http://www.flickr.com/photos/36383814@N00/6948262808

What it does is read all the control points in an existing PTO
project, and use these to generate a 'morph' distortion for each
photo that results in all the control points lining up exactly.

The morphing itself is done with ImageMagick.

I'd describe this as experimental, it isn't going to work with HDR,
may do strange things with masks and circular cropping, and probably
doesn't work on Windows.  I'd like to hear some feedback, do you
think something like this would be useful in Hugin?  Is there a
better approach than forcing _all_ the control points to fit?

To try it you need the current Panotools::Script from SVN, something
like this:

   svn co https://panotools.svn.sourceforge.net/svnroot/panotools/trunk/Panotoo...

..or wait for the Panotools::Script 0.27 release (not sure when that
will be).

--
Bruno