After a short sprint at SciPy 2009, we've put together the infrastructure for an Image Processing SciKit. The source code  and documentatin  is available online. WIth the infrastructure in place, the next focus will be on getting contributions (listed at ) merged.
If you have code for generally useful image processing algorithms available, please consider contributing. Feel free to join further discussions on the scikit mailing list .
Kind regards Stéfan