Actionscript books saw a 22% increase in sales and increased their market share in the programming languages category. Web design and development was interesting because "Flash" stayed pretty stagnant at 2% growth (though it's share of total sales was impressive). Flex on the other hand, grew at an amazing 42% and looks like it's becoming a bigger chunk of the web design and development market. Keep in mind that most of the Flex books aren't even out yet.
Another thing that struck me was the plummeting of traditionally desktop programming languages: Visual Basic, C/C++, ect. Java even took a plunge which when looking at the bigger picture is a good indication that interest continues to move into the web. And the fact that RIA books have grown by so much means there is a lot of interest in building richer web experiences. I'm looking forward to seeing these maps next year when more RIA technologies have been released and written about.