10 Rules For Efficient Form Design
Nick Babich

As pentool noticed, form used as a best-example for one best-practice breaks couple of other rules. Just take a look at Facebook’s Sign Up form used as an example for highlighting errors. Of course it isn’t Nick Babich fault, it’s just difficult to find well designed forms.

I think it shows that all the best practices have little impact on conversion of simple forms and when it comes to design of complex forms, there are usually bigger issues than placement of labels etc.

That being said — most of Nick’s points are valid.