Today we’re releasing the Dart SDK 1.0, a cross-browser, open source toolkit for structured web applications. In the two years since we first announced Dart, we’ve been working closely with early adopters to mature the project and grow the community. This release marks Dart's transition to a production-ready option for web developers.

The Dart SDK 1.0 includes everything you need to write structured web applications: a simple yet powerful programming language, robust tools, and comprehensive core libraries. Together, these pieces can help make your development workflow simpler, faster, and more scalable as your projects grow from a few scripts to full-fledged web applications.
Google Releases Dart SDK 1.0 For Structured Web Applications [blog.chromium.org]