I am using a USB adapter, Realtek 8188CUS with Ubuntu 10.04.3. If I install the software supplied by Realtek, the interface works beautifully. When I reboot, the wireless disappears, and it requires a reload of the driver.
I'm relatively new to Ubuntu, but have searched for this problem on the wireless help sites, and haven't seen this problem mentioned. Every time I reload the driver, I get the error message that 8192CU (the driver) isn't in /proc/modules. Don't know what that means, or if it is significant at all. That is the only error I am getting, though, and it runs great after that.