The DimDim documentation says the new Moodle Integration pack (5.5) is good for Moodle versions 1.8.x.
I cleaned out the old version on my backup Moodle and when I try to install the new integration pack it tells me...
Module "dimdim" (2010031000) could not be installed. It requires a newer version of Moodle (currently you are using 2007101520, you need 2007101580).
I'm running 1.9.2+.
On http://docs.moodle.org/en/Moodle_version ther's an example of a version.php file that luckily shows version 2007101580. I think the documentation should say the v5.5 integration pack is good for 1.9.8+ (Build: 20100512). Correct me if I'm wrong on this though.
Paul