… did you know that the PubMan you know (http://pubman.mpdl.mpg.de/) is not the only one of its kind?
Currently the MPG PubMan has three more siblings:

National Institute for Materials Science (NIMS), Tsukuba, Japan
http://escidoc.jp/

Geo-Forschungs-Zentrum (GFZ), Potsdam, Germany
http://ebooks.gfz-potsdam.de/

PEER Project Installation (http://www.peerproject.eu/)
http://peer.mpdl.mpg.de/pubman

And we can benefit from all these other installations by
… getting feedback on experiences in using/installing PubMan
… hints on existing bugs
… ideas for new features
… and manpower for further development.

Additionally we get more and more feedback on our mailing lists from people who are currently installing PubMan for evaluation.