Just feedback on windows7. I tried the tests inside IDLE and done 'Run Module' (F5) (deleting the directories between tests):

test_A:

import os, shutil
os.makedirs('foo')
os.makedirs('bar/boo')
shutil.move('foo/', 'bar/')

test_B:

import os, shutil
os.makedirs('foo')
os.makedirs('bar/boo')
shutil.move('foo', 'bar/')

and finally test_C:

import os, shutil
os.makedirs('foo')
os.makedirs('bar/boo')
shutil.move('foo\\', 'bar/')


... and got the same traceback:

Python 2.7.6 (default, Nov 10 2013, 19:24:18) [MSC v.1500 32 bit (Intel)] on win32
Type "copyright", "credits" or "license()" for more information.
>>> ================================ RESTART ================================
>>> 

Traceback (most recent call last):
  File "D:\temp\test.py", line 4, in <module>
    shutil.move('foo/','bar/')
  File "D:\programs\Python27\lib\shutil.py", line 291, in move
    raise Error, "Destination path '%s' already exists" % real_dst
Error: Destination path 'bar/' already exists
>>>