My wife has a copy of this at home, and as I am new to Rails, but working in Rails 3, wondering if this book is still worth the investment, since it has been a few years since it came out, and I understand there are quite a few changes.

Try
The Well-Grounded Rubyist
Covering Ruby 1.9
David A. Black
http://www.manning.com/black2/
May, 2009 | 520 pages
ISBN: 1933988657

it's more recent and rather good written

I bought the book at half price
http://archive.constantcontact.com/fs172/1101335703814/archive/1112008583363.html
with the Promotional Code dotd1231 and reading right now