And here is new performance patch (Victor's patch was outdated because of heavy changes incorporated from Unladen Swallow). Results of bench_pickle.py are as follows:

* Python 2.7 (cPickle):

Protocol 0
- dump: 189.8 ms
- load (seekable=False): 318.1 ms
- load (seekable=True): 321.2 ms
Protocol 1
- dump: 58.2 ms
- load (seekable=False): 89.5 ms
- load (seekable=True): 89.4 ms
Protocol 2
- dump: 58.0 ms
- load (seekable=False): 89.1 ms
- load (seekable=True): 89.1 ms

* Python 3.2 (unpatched):

Protocol 0
- dump: 144.5 ms
- load (seekable=False): 530.7 ms
- load (seekable=True): 530.5 ms
Protocol 1
- dump: 27.8 ms
- load (seekable=False): 280.4 ms
- load (seekable=True): 279.9 ms
Protocol 2
- dump: 27.8 ms
- load (seekable=False): 280.6 ms
- load (seekable=True): 281.9 ms

* Python 3.2 + patch:

Protocol 0
- dump: 146.4 ms
- load (seekable=False): 611.1 ms
- load (seekable=True): 194.2 ms
Protocol 1
- dump: 27.3 ms
- load (seekable=False): 254.7 ms
- load (seekable=True): 31.2 ms
Protocol 2
- dump: 27.3 ms
- load (seekable=False): 254.6 ms
- load (seekable=True): 31.2 ms