Can you push PyDev 2.0 to Aptana Studio 3? The official download page still has 1.6.5, the nightly has 1.7.
Hopefully a new release should be available later this week (although I think the nightly is already on 2.0 - from where are you getting it?)
I've used http://nightly.aptana.com/nightly/studio3 which is still at 1.7.0.
It seems that URL is outdated (I'll have to update the PyDev homepage too). Please read the instructions at: http://wiki.appcelerator.org/display/tis/Changing+the+Update+Type to get the latest nightly of Aptana Studio 3.
Thanks, that worked and installed the latest PyDev.