Actually I didn't like it at all. It's been a few years, but it totally put me off learning Haskell. Doing some small steps again now, but although I'm usually all for real world applications first (instead of doing the millionth factorial function) - but it did not make much sense to me didactically.

The authors put the book online; though they prefer you purchase a copy if you like it:

http://book.realworldhaskell.org/read/index.html