In the spring before C# was first disclosed, I ended up, through a curious juxtaposition of events, writing a book on C# named "A Programmer's Introduction to C#"
This probably rates second on the list of "cool things I got to do while I was on the C# team" (being on the language design team probably rates #1. Talking to customers at PDC in Orlando that year is a probable #3...)
When it came out, it was certainly one of the top two C# books around, since there were only two books. As we changed things in the language and runtime and I expanded my understanding, I worked on the second edition, which came out around Beta 2, and had a cover that proudly claimed "Based on Beta 2" (which may be covered up with a sticker on your version).
Time passed, other good C# books were written, and with my move into the PM role, I found I didn't have much motivation towards doing an update of the book, so it became dated.
This troubled me. Though there are certainly problems with my book, it was still a pretty good resource, and my lack of motivation meant that it might fade away totally. Except for the effort of my extremely patient publisher, Gary Cornell of Apress.
Gary enlisted Nick Wienholt, MVP and author of Maximizing .Net Performance to modify the book to address the Whidbey enhancements to the language. I'm pretty excited about this - I get some say in what gets changed in the book without putting in a lot of effort (books are huge time sinks).