Nice design - shouldn't be too surprising for a design-oriented site. But it's a pleasing and simple use of Blueprint CSS. Just one question: I don't understan

Nice design - shouldn't be too surprising for a design-oriented site. But it's a pleasing and simple use of Blueprint CSS. Just one question: I don't understand why Wufoo Form Builder was needed for the signup flow. Why not just add a form of your own? Or am I misunderstanding why Wufoo was mentioned at the end of the signup process?