Does that include the 57x57 icons though? As several people have pointed out, most of the icons you posted won't scale down, whereas Apple and Co may have some beautiful hi-res icons but also completely re-do them for smaller display.
Yes it did in my enquiries. I hired one of the guys and he produced the full set of icons, making changes to all the sizes to make sure they looked good on the phone.
In the Apple ecosystem, you need a commitment to good design. It's less strong than it used to be (for example read John Siracusa and early Gruber criticising Apple's design choices with in OSX or Pierre Igot taking every app he comes across to task). But it's always been a defining point of playing in the Apple world, ever since Steve Jobs mentioned his calligraphy classes.
I think it's a gross overestimation. There are plenty of good designers who will do work for a lot less than that. I had an entire iPad app design done for around $300 (icon, table background, custom table cells) and I recently got another design done for an app for $100 (icon, splash screen, custom tab bar backgrounds, custom nav bar backgrounds, custom table backgrounds).
The price also included the splash screen, custom tab bar, table backgrounds, custom navbar. I could probably get better if I paid $800-1000 but I think that this is good enough.
I think this is a gross underestimation of how much these designs would cost. Does anyone have any real data on the cost of iOS icon design?