Automattic supports WordPress.com VIP, a premium service designed for large scale enterprises.
WordPress.com VIP combines the benefits of WordPress.com and the ability to run custom code. In addition, WordPress.com VIP offers companies a robust CMS and 24/7 service. Other products and service available include site and security monitoring, content monitoring and developer training.
Current WordPress.com VIP clients include: AllThingsD, CBS, CNN, GigaOM, InStyle, Kaiser Family Foundation, NBC Sports, the New York Post, TED, TechCrunch, Quartz, and many more.