Just wanted to say this. Having bought and read many Flex & actionScript books over the years, I hadn't really given Adobes documentation much of a look (apart from the liveDocs that is, which I couldn't live without.). Well, I had a free afternoon today, so I thought I'd have a read through the new Flex Builder 3 PDFs.
So, 1000s of pages and a whole day later I've come to the conclusion that they're amazing. Easily the best 'book' on Flex I've read. So much so, I'm going to order a printed copy of the documentation set in the morning. It's easy to overlook this source of information, and think it's essential to look at 3rd party books to teach you this product. I'd just like to say to both new and seasoned users, that Adobes Flex PDF collection is something not to be ignored. I often see post's asking 'which is the best book on Flex, I now think that you can't do better than Adobes own documentation. Here's a link. http://www.adobe.com/support/documentation/en/flex/