For OS X you can use Color Oracle (http://colororacle.cartography.ch/) or Sim Daltonism (http://michelf.com/projects/sim-daltonism/) to see your designs as a person with various types of color blindness would. I would hope that such software exists on other platforms, but I’ve never checked.

I truly appreciate this. Being colorblind myself I see the value right away. Sometimes is very hard to figure something out on a website.

The site suggest using colors with more contrast.

Colorblindness comes in all levels so this is somewhat ambiguous. I believe the best way to help colorblind users is trough the use of different figures and mouse hovers.

As a designer you don't have to think about new color schemes, just additional reference points.

Very fascinating! According to the website 8% of the male population is colorblind. On a major website that could equate to a fairly large number of users.

The examples on the blog are clearly defined and annotated to explain why they are good or bad. As a web developer I will have to keep this site in mind.

Well, some of their examples suggested they aim for fully color blind people. Their numbers are tiny.

Most color blind people can recognise colours, they just have this ability restricted. So they should be actually be offering safe color schemes instead of pecking everyone who just happened to use colors.