Both the Acer Aspire One and MSI Wind U100 are being sold now with 3-cell battery or 6-cell battery. The official ratings for the battery life are about 3 hours for the 3-cell battery and 7 hours for the 6-cell. I don’t know how they measured that, but we just turned on and left all three of them connected to a WiFi local network, and the results were as follows: about 2 hours and 20 minutes for the MSI Wind U100, 2 hours and a half for the Acer Aspire One and almost 3 hours for the Asus EEE PC 701. Maybe the Intel Atom consumes much less battery than the Intel Celeron of the Asus’s, but the reason the Asus showed better results are because it doesn’t have a mechanical hard drive, which eats some more battery than a solid flash memory disk. Also the 7″ inch display has less consumption and it has 4-cell battery instead of the 3-cell of MSI’s and Acer’s.
I didn’t have in mind to compare the Asus on a head-to-head comparison with the two Atom netbooks, but since the results are tied on those two and the Asus has noticeable difference in battery consumption I must say it’s the winner here.
1st: Asus Eee PC
2nd: Acer Aspire One
3rd: MSI Wind U100