Om is really cool and David Nolen is an awesome member of the Clojure community. However, I've played around with Om and found it to be a rather complex tool. I think it would be perfect for a high performance web app where I need to control everything - but thats not what I generally need.

I've enjoyed working with Reagent, which is another react clojurescript interface. It sacrifices some very minor functionality for an extreme decrease in complexity. It's actually enjoyable to make a UI with it.