Compare to the Firefox, I prefer to run Chromium in my netbook. This is because the screen of the netbook is small, and the resolution is low. Using Firefox, the toolbars and file menu already occupies half of the screen. I think Firefox 4.0 will solve my problem.
Then, using Firefox on the netbook with Ubuntu, playing Castle Age will make Firefox slow down. May be the reason is the netbook memory is smaller than normal laptop.
However, I am still using Firefox on Ubuntu. Because of the powerful extensions on Firefox, such as DownThemAll, FlashGot, etc.