I don't find mine too dim, I've got the brightness on the lowest setting & would like it even darker. Over 50% brightness starts to give me a headache.
I think it depends a lot on ambient lighting. Perhaps the screen is just very sensitive to glare. I sit next to a window, and as I type right now at night, the screen is plenty bright; however, during the day, it has trouble competing with the daylight from the window (and I do not mean direct sunlight, but just ambient light.)