I got similar results on 64bits for my original patch (very similar to what Serhiy used now). The numbers are not really conclusive.

Report on Linux leppy 3.13.0-46-generic #77-Ubuntu SMP Mon Mar 2 18:23:39 UTC 2015 x86_64 x86_64
Total CPU cores: 4

### 2to3 ###
6.885334 -> 6.829016: 1.01x faster

### etree_process ###
Min: 0.249504 -> 0.253876: 1.02x slower
Med: 0.252730 -> 0.258274: 1.02x slower
Avg: 0.254332 -> 0.261100: 1.03x slower
Significant (t=-5.99)
Stddev: 0.00478 -> 0.00640: 1.3391x larger

### fastpickle ###
Min: 0.402085 -> 0.416765: 1.04x slower
Med: 0.405595 -> 0.424729: 1.05x slower
Avg: 0.405882 -> 0.429707: 1.06x slower
Significant (t=-12.45)
Stddev: 0.00228 -> 0.01334: 5.8585x larger

### json_dump_v2 ###
Min: 2.611031 -> 2.522507: 1.04x faster
Med: 2.678369 -> 2.544085: 1.05x faster
Avg: 2.706089 -> 2.552111: 1.06x faster
Significant (t=10.40)
Stddev: 0.09551 -> 0.04290: 2.2265x smaller

### nbody ###
Min: 0.217901 -> 0.214968: 1.01x faster
Med: 0.224340 -> 0.216781: 1.03x faster
Avg: 0.226012 -> 0.216981: 1.04x faster
Significant (t=6.03)
Stddev: 0.01049 -> 0.00142: 7.4102x smaller

### regex_v8 ###
Min: 0.040856 -> 0.039377: 1.04x faster
Med: 0.041847 -> 0.040082: 1.04x faster
Avg: 0.042468 -> 0.040726: 1.04x faster
Significant (t=3.20)
Stddev: 0.00291 -> 0.00252: 1.1549x smaller

The following not significant results are hidden, use -v to show them:
etree_generate, etree_iterparse, etree_parse, fastunpickle, json_load.