After two years of delays, Apple's (AAPL) reinvented Siri, Siri AI, appears ready for primetime. The company unveiled the AI-powered version of its assistant at its Worldwide Developers Conference in Cupertino, Calif., on Monday, saying it will launch, albeit as a beta, later this year. The update is designed to transform Siri from a glorified kitchen timer to a digital helper for the AI age.