and WordPress in terms of social features & flexibility (like categorization, ACL, media management etc.) but it's got (by far) the best API there is & it's the easiest to use for almost any web project
ajax-based front-end editing for managing items & moderating comments (user toolbar) automated user profile pages (blogs) “versatile” modules fetch everything from K2 (items, videos, images, comments, tags, categories, users etc.) powerful search capabilities (search on all or specific categories or use “Google AJAX Search” integration)
extension to setup & style... parameters control EVERY element you see no “menu itemid” headaches to worry about uses 1 master CSS file only for everything MVC overrides are easier (simply copy the component “templates” folder or the module sub-templates in your Joomla! template's html overrides folder) module “sub-templates” allow for totally different layouts of the same module
or small news portals/magazines with author blogs, comments, tags etc. any type of catalog (products, documents, downloads, work portfolio etc.) blog knowledge base directory listing (events, classifieds/ads, business directory, contacts etc.) sitemap
in the Joomla! community...” more than HALF A MILLION downloads since March 2009 supported by all major template clubs (16+) 200+ K2 related extensions in the JED translated in multiple languages used in thousands of websites K2 powers some of the most prominent & high-traffic Joomla! websites worldwide Google loves K2 sites (thanks to unicode URLs) easy content migration between major Joomla! versions
category "template" with pre-assigned parameters and using it for rapidly creating complex tree-like structured nested categories K2 Plugin API to extend forms beyond classic CCK Built-in K2 extended caching Performance! Easy content migration to Joomla! 1.6, 1.7...