This is purely a bug fix release, so be sure to update if you're using Preact 4.x.

Bugs Fixed:

• Fix orphaned keyed VNodes not being removed in certain cases, such as when there are adjacent non-orphaned non-keyed VNodes (see developit/preact-compat#21)
• When diffing a component against a non-component VNode, if the component render returns a different DOM node, make sure to reclaim the original node. (Issue #73)

• Preact 4 is now officially out of beta. Please still report any bugs you find!
• setState() callbacks should be called with the component as their context.

• Fix multiple camelCase'd CSS properties (#66)
• Fix child component refs not being invoked with null when the associated component is unmounted
• Fix high order component refs linking to parent component when they should link to the child component/node.

• Cancel preliminary support for String refs. Preact core will only be supporting function refs, since String refs are "mostly" deprecated.

• Add support for refs!
• Add support for defaultProps (static property on Components)
• Possibly Breaking Change: cache rendered DOM with components when recycling
• Possibly Breaking Change: don't wipe recycled DOM nodes, simply diff when re-used
• Use setImmediate() to improve setState() performance where available
• Skip empty values when serializing style objects
• Coerce falsey className and style values to an empty string to avoid class="null" and style="null"
• Rename missing component insert from <x-undefined-element> to <undefined>
• Use a Symbol for storing the prop cache where available

• Fix for key behaviour, and don't write keys to the DOM as attributes.

• Performance tuning for a ~10% improvement on DBMonster (basically 10% faster diff algorithm)
• Refactored diff algorithm to be easier to follow
• Add Component.prototype.forceUpdate() method.
• Fix a bug where a child component of a high-order component self-rendering (eg: via setState()) would cause a subsequent re-render of the parent component to re-initialize itself and the child (through the recycler, but this was causing thrash).
• Fix an issue where nested components would not receive unmount lifecycle hooks (fixes Issue #47)

• Bugfix: pass context through recycled constructors (with this react-redux is now fully supported!)
• linkState() when used with top-level keys (ie, not dot-notated) will no longer mutate this.state in-place.

  (Nested keys can and will still mutate this.state, since the implementation of immutable state traversal would essentially be a small immutability library, not something Preact core can justify)

This is likely the last beta release of Preact 3.0, it'll become the stable branch shortly. Feedback and testing welcome!

• Use a safeguard method to obtain preact attr cache objects before writes
• Fix edge case where fallthrough attribute values would not be stored in the preact attr cache
• null instead of delete for _component refs, avoiding shape mutations
• build tweaks

• Preact's codebase has been factored into modules
• Reduced possible repaints by collecting property cache into a namespace
• 10-20% performance improvement under heavy rendering load!
• Now available in npm under a nice dist-tag: npm install preact@beta

• Fixes for event removal (#34), tests.

Beta version of the 3.0.0 major bump:

3.0.0

• Added context support
• Bugfix: componentDidUpdate() should not be called after initial render
• Switch from tracking nextState to tracking prevState
• Drop VNode#__isVNode in favor of instanceof (reason)

• Performance improvements for asymmetric DOM properties
• Account for external mutation of properties

• Fixes #5: props are now passed to Component constructors.

• Fix: ensure the npm package includes src/ since it's now used by anyone using rollup for bundling (via jsnext:main).

• Switch to a rollup-powered build, courtesty of @sheepsteak (thanks!)
• Apply more strict linting around the codebase, removed some unused code. General cleanliness += 1.

• Fix incorrect behavior where attributes with explicit false values were being skipped.
• Readme updates as ever.

• Fix componentWillMount / componentWillUnmount for high-order components

• Fix detachment of content attributes by preferring their property equivalents where available

Re-add component.setProps() since other libs depend on it

• Preact 2.0.0 adds support for High-Order Components (yay!)
• Redues the filesize by ~300b