The cat is out of the bag: my forthcoming book on Rails, grandly entitled Ruby on Rails Enterprise Application Development: Plan, Program, Extend, is now being advertised for pre-orders on the Packt website. I was keen on calling the book Rails in Context, as to my mind that is the book's strength: showing Rails in a realistic context, working with other tools. (No one else liked that title, though.) The book is not intended as a replacement for the classic Agile Development with Rails, but more as a complement to the excellent reference material that book and others provide.
The focus of the book is on building a Rails application in the context of a small business: setting up a realistic SME infrastructure for Rails, an overview of how to develop with Rails, installing and configuring a Subversion server, unit testing, using Ruby to write scripts for data import, deployment using Capistrano, and some simple techniques for improving performance using caching and load-balancing (Apache + Mongrel). The result is a simple contact management system with tasks and file uploads, which is dog-ugly but practical. If you want to see it for yourself, you can check it out from my public Subversion repository with:
svn co http://svn.receptacular.org/Intranet/trunk
I didn't write the book all on my own: I was ably partnered by Rob Nichols, a friend I met through OpenAdvantage. It's taken just over a year to write, and has been killing me in the evenings during that time, even though I only had to do 5 chapters. I think it was worth the effort, and I'm pretty pleased with the result (as pleased as a perfectionist can be). (By the way, if you're thinking of writing a book, let me reiterate what everyone says: it's hard, and probably not very lucrative from a cash perspective. I did it because I've always wanted to have a book published and I enjoy writing.)
Go and buy it. If you pre-order it now, you'll even get a discount!