Watir is rapidly attracting users. (We pronounce it 'water'.)
Many of our users are new to Ruby and even new to object-oriented languages.
In fact, they can't tell where Watir ends and Ruby begins. Thus, they end up asking lots of questions to the Watir mailing list (firstname.lastname@example.org) that are really just Ruby questions.
I gave a presentation of Watir's precursor at the Ruby Conference 2003 in Austin. At that time, i said that we were using Ruby as our scripting language because it was intuitive and easy to learn for non-programmers.
But now they are wanting to read data from spreadsheets or csv files or initialization files. Or they want to create libraries. Or they want help with Test::Unit.
I consider myself middling in my Ruby skills. I've heard meta-classes explained at least three times and still don't understand them. But i'm one of the more knowledgable people on the list.
We could use your help. If you are interested in helping new users learn how to use Ruby, please consider joining our mailing list. (Or you could just help Brian with his book.)
Oh, and BTW, we now have a gem for Watir ('gem install watir'). It has unit tests and rdoc. And yes, Watir only works on Windows and only with Internet Explorer. I offer apologies to the OSS gods.