In a previous post I published benchmarks comparing the new Intel Atom N450 to the Atom N270 and N280, the conclusion was that all three netbook processors got a very similar performance level. The Atom Pineview/Pine Trail architecture is a significant integration step allowing lower power consumption and lower price, a minimum performance boost is expected for the Atom N470, clocked at 1,86GHz (200MHz higher than Atom N280).
Anandtech published a very nice article benchmarking the Asus EEE PC 1005PE (Atom N450) vs the topseller EEE PC 1005HA (Aton N280)
I cite Anantech: "1005PE is slightly faster than the 1005HA. The difference in most of the tests is hardly worth discussing (1-2%)".
The 1005PE got much better results in the DivX encoding test, however it seems that this is due to the fact that the performance boost is due solely to the operating system (Windows 7 for 1005PE and Windows XP for 1005HA). This seems to be confirmed by the fact that the netbook with Dual core Atom 330 (EEE PC 1201N and Windows 7) got a 120% improvement vs the EEE PC 1005HA (Atom N280): "but in the DivX encoding test we see a whopping 63% increase. This might be another Windows 7 vs. XP difference, as the 1201N performance relative to the 1005HA is a 120% increase, which obviously shouldn't happen if you just double the core count.".