In our initial testing of Moodle 2.0 (upgrading from 1.9.8), no gradebook with more than a few items displays in such a way that we can see the total grade for the student.
There is no scrollbar and no way to see grades that are wider than the screen, which affect most of our established courses with any more than a few items.
This may be related to the fix of
I put this as a blocker as one of most important tests of Moodle 2.0 is that it does not affect the grades of imported or updated 1.9.8 courses and sites, and is the first thing people will check.
I have confirmed that this is a problem when creating a new course and adding a few assignments.