Doc nits:

* "items are returned in the order they were first added": it should be
made clear that it matters when the *key* was first added
* "An *OrderedDict* remembers order that entries were inserted": misses
a word somewhere?
* "OrderDict" should be "OrderedDict"
* "compare their ordered :attr:`items` list": ... lists?

Implementation nits:

* "raise TypeError('expected at 1 argument, got %d', len(args))"
  should read "at most" and use "%" instead of ","
* "raise KeyError" in popitem(): should it get a message?
* eval()ing the repr() will not construct the dict in the same order