Jeff Barr is Amazon’s Web Services evangelist. He’s talking about all the web services that Amazon offer. Feels like a product pitch, even though the technology is interesting.
Some of the demos that use the E-Commerce API are pretty cool. I love the flash demo that shows band relationships.
The mechanical turk is also a stunningly cool idea. It’s all about creating marketplaces… Well, apart from thesheepmarket.com perhaps. 
I hadn’t seen EC2 before either. It’s kind of rent-a-Xen. It’s still in Beta right now.