Wptp-Chocolate has good design - not amazing - and is ready for a web2.0-ish informational blog. Lots of room for navigation and advertising makes the theme great for an affiliate marketer who is offering tons of content to bring in users. The menu in the header is nice, and the links stand out which makes the navigation obvious adding to the overall usability of the theme. Moses, the themes author has added great functionality and has apparently added some features based on user input.
DivGrad is a really nice theme. The layout is easy on the eyes, and very sleek. The rounded corners are a little big, but this works for a web2.0 style blog. Easy to find RSS and Home buttons in the header, and a nice color scheme top of this blogs list of worthy design features.