WordPress Core is what we call the WordPress software.
It’s open-source, which means it’s developed by a community of developers around the world and new versions are released 3-4 times a year with new features and bug fixes.
WordPress Core Release Cycle
Betas → Release Candidates → Final Release
WordPress.com is the biggest WordPress site on the web, with millions of users. Engineers at Automattic have added hundreds of extra features on top of core WordPress that help with performance, SEO, security, social network integration, and more.
In addition, WordPress.com’s global, rock-solid infrastructure scales up effortlessly and invisibly, ready for high traffic at any time.
WordPress.com VIP lives on the WordPress.com infrastructure. In addition to the features made available on the WordPress.com platform for every user, the WordPress.com VIP team has vetted and built hundreds of additional features as plugins just for VIPs. WordPress.com VIP has a dedicated team of engineers and support staff whose sole objective is growing and maintaining the best cloud hosting platform for WordPress sites in the world.
WordPress.com VIP is always running the latest version of WordPress, which means integrating new features and improvements as soon as they are available. VIP clients are always on the forefront of each new WordPress release and, in turn, this helps strengthen your site’s core experience as security and performance improvements are applied to your codebase seamlessly and behind-the-scenes.