Changelog

0.4.0

Breaking change: Component functions can get arbitrary arguments, and not just vectors and maps. This is a breaking change, but behaviour is unchanged if you pass a map as the first argument (as in all the examples in the old documentation).
React updated to 0.9.0.
You can now use any object that satisfies ifn? as a component function, and not just plain functions. That includes functions defined with deftype, defrecord, etc, as well as collections like maps.
reagent.core/set-state and reagent.core/replace-state are now implemented using a reagent.core/atom, and are consequently async.
Keys associated with items in a seq (e.g ”dynamic children” in React parlance) can now be specified with meta-data, as well as with a :key item in the first parameter as before. In other words, these two forms are now equivalent: ^{:key foo} [:li bar] and [:li {:key foo} bar].
Performance has been improved. For example, there is now practically no overhead for tracking derefs in components that don’t use atoms. Allocations and memory use have also been reduced.
Intro and examples have been tweaked a little to take advantage of the new calling conventions.

Changes in application state are now rendered asynchronously, using requestAnimationFrame.
Reagent now does proper batching of updates corresponding to changed atoms, i.e parents are rendered before children, and children are only re-rendered once.
Add reagent.core/flush to render changes immediately.
Bugfix: Allow dynamic id with hiccup-style class names.