Om and React are cool, but this comparison is disingenuous. The author should have compared the Om implementation to a native (JS) React implementation.

I recently converted a React project to Om and found it to be a very enjoyable exercise. However, contrary to most tweets/blog posts, my Om code ran slower than the JavaScript version, which ultimately caused me to abandon the conversion. Full disclosure, the port was a naive implementation of a single page React component which probably wasn't the best use-case for Om ( (om/transact! ...) was causing a full page re-render to the VDOM).

Om/cljs is very beautiful and concise compared to JS ... immutability rocks! If I could achieve performance comparable to JS I'd switch in a heartbeat.