Well, it has started to show up on the Apress website, so I believe that means there is no use in hiding it any longer. Jon and I (along with our co-author, Kevin Marshall) are currently hard at work on book for Apress, entitled Pro ActiveRecord for Ruby: Databases with Ruby and Rails.
The book will focus solely on ActiveRecord, both inside and outside of Rails, and seeks to be a complete reference for ActiveRecord.
Well, with that out of the way, I'm currently working on the Common Questions and Howtos chapter, which is the chapter that contains all of the juicy tidbits and edge cases that don't fit well into their own chapters, and if anyone out there has any ideas of things they'd like to see covered there, I'd be really interested to hear them. I've currently got some info on using multiple databases, how to handle localization, using composite primary keys, using GUID/UUID keys, and some other things along those lines - I'd love to hear if there is anything you think might be of value for both new users, experts and everyone in between.