Is design dead?

For me, the design isn't dead, for XP the good design will appear if you listen to your code. Like I had said before I like the references between architects and programmers, and here it appears again. For a more simpler and cleaner code, you may split into teams and those teams will have only one job. The idea of coding in blocks it's something that will help you a lot when coding. It will save you some money in the future, as we know, a change in the analysis phase will cost a hundred time less than in the production phase. 

YAGNI (you ain't gonna need it) Every coder have heard at least one time this phrase, maybe if you're starting to code it won't have any sense, but as you start coding more and more you will find this phrase your best friend. XP focus in the present rather than in the future (sometimes) they will advise you to code what you will need that iteration. Don't code what you will use for n-iterations even if it's free. Why did I write in parenthesis sometimes? Well in the text it mentions that it's easier to refract over-design than to no-design code. To accomplish that you will need two at least two factors, have a good pattern and think towards the future.

This brings me to the topic of patterns, GOF gave us an amazing book of how and when to implement patterns in our code, grasping the patterns will make your life much easier as you may think. XP design look for a good knowledge of the patterns, not only knowing them but being able in how to implement correctly. The phrase "Real XPerts do not do diagrams" I think it's a huge mistake, a good coder needs to be able to communicate with every team, and diagrams will help a lot with this like Martin said, you just need to draw the important classes and its main methods and attributes.