.com blogs vs .org sites

wordpress.com is the blog host from Automattic, the developers behind the platform.

Sign up for a free 3 GB space with a URL such as someblog.wordpress.com and you can choose from a limited pool of themes and widgets, create pages and posts, receive and manage comments, and upload some media types. You can pay to upgrade for things such as adding space, enabling video uploads, removing those ads that Automattic sticks on sites or even to use your-own-domain-name.tld.

wordpress.org is where the standalone or self-hosted alternative to Automattic's hosting can be downloaded and discussed, along with most of the plugins that extend the blogging platform into what can be an awesomely powerful content management system.

.org downloads are installed (else bypassed using one-click installers such as Fantastico which gets a warning shot in Chapter 7) on shared, VPS, or dedicated servers. The main downside to scalability is the responsibility you assume to secure your site...