> The developer(s) are slow about incrementing the allowed versions.
> Literally all you have to do to make it work (usually) is vim ~/.mozilla/firefox/yourprofile/extensions/whatever.xpi, then type /install.rdf, hit enter twice, edit <em:maxVersion>n</em:maxVersion> to be +1, then hit :x and you're done.
Can you (or anyone else) explain why the developers hesitate to fix this problem officially? Like you said, it is rather simple to fix.
Even though most of us on HN are able to apply the fix ourselves, integrating the fix to the official pentadactyl extension would save time for everyone that wants to try or install pentadactyl.