This isn't really a React-specific tip, as such anti-patterns often occur in code in general; in this case, React simply points them out more clearly.

Updating: componentWillUpdate void componentWillUpdate( object nextProps, object nextState

React.isValidElement boolean isValidElement(* object) Verifies

ReactTestUtils makes it easy to test React components in the testing framework of your choice (we use

React.PropTypes React.PropTypes includes types that can be used with a component's propTypes object to validate props

React.createClass ReactClass createClass(object specification)

ReactDOMServer.renderToStaticMarkup string renderToStaticMarkup(ReactElement element)

ReactDOM.findDOMNode DOMElement findDOMNode(ReactComponent component)

statics object statics The statics

replaceProps void replaceProps( object nextProps, [function callback] )