Used it and loved it when it was the mobile app landing page service, paid the $50 for the new reincarnation during the backing phase -- never used it since. Wish I got my money back, actually.
First and foremost, congrats on shipping - that's the hard part. As per the product, the UI looks pretty good for a MVP - I would probably polish it up a bit.
I only seriously took a hard look at Heroku in the past week and for what you get — I think it's absolutely fantastic. You can't beat the free, unlimited web dyno vs. AWS's free-for-one-year micro instance.
Cool, once you gain traction, I would definitely explore partnering with an OEM to get your application preloaded and work out some kind of deal that way. I think it would be a hit.
I totally agree with you. If I had to guess, I think it's going to be the way you described it — pick one of these socks from 5 pairs, great, Blake approved!
Don't do it for the money — 99% of startups fail. That's not to say that you might not fall into the 1%. Someone's gotta hit it big once in a while, right?
Do it because you love what you do and are passionate about it. Too many people failed trying to chase money. Don't make the mistake of doing a startup for the wrong reason.