16:10 is a standard ratio. 1680x1050, 1280x800, 1920x1200...
Looks like I got my math wrong. I just noticed that 8:5 is the same as 16:10 =p
What's a "standard"? 16:10 is as much a standard as anything else. The only reason 16:9 is used is because TV screens use it, so mass production reduces cost for monitors as well. It doesn't mean that 16:9 is better or a standard more than 16:10.