There has always been, and will always be, the strenuous balance of function vs. form. Whether it's a website or an application, at one point you need to decide whether you'll start with "how it looks," or "how it works." You can't do both at the same time. (No, you can't.)

John Gruber writes a column about tech news (though generally related to Apple), and I think he's got it figured out:

"Figure out the absolute least you need to do to implement the idea, do just that, and then polish the hell out of the experience."

http://daringfireball.net/2008/11/iphone_likeness