LYAH is a chore. I got nowhere with it - it is tedious. After a cursory glance a few of us at my company are working through The Little MLer in Haskell instead. It seems to really be focussing on types and I think those kind of core concepts are important to grasp at the early stages.
More importantly, the Little Schemer and The Little MLer are aimed at non-programmers... yet programmers struggle with them. We should question why that is.