iPhone App store didn't have web sites for the longest time, but I think they changed it recently. Although it is still hard to find - I have seen web links to apps, but have been unable to create them myself.

Btw another silly trap with the Android Marketplace: apparently they only show you the comments in the language of your phone settings. A friend of mine has created a German language app, but his phone is set to English. It was only a couple of weeks later that he discovered there already were several comments for his app.