Wufoo and Likewithyou are doing it themselves. They have design backgrounds. Loopt is now a big co and presumably paid a good design firm. I think Scribd has an outside designer too.
That is not true. Ricky Pernikoff is a rockstar.
I wouldn't put Scribd on that list personally. But from what I hear they're working on bettering what they have. Plus with all that traffic I doubt they'd be too worried.
Wufoo as far as I know was designed by one of their team members who came from a design/usability background. They started a magazine called ParticleTree(http://particletree.com/) before launching Wufoo.
-Zaid
I listed Scribd more for the fact that their usability is really on point. I especially like the upload box on the front page. I'm glad to see more hacker types are putting time into making the user experience really good.
Also, I'd seen Particle Tree before. Definitely well-designed.
I'm guessing folks aren't doing the design themselves? If not who is?