Sun introduced JavaBeans as a coding convention through which java classes can participate with visual component assembly tools (WhatAreComponentsAnyway). While successful, Sun confused the world by introducing a second set of interfaces for server side components called EnterpriseJavaBeans.
To make things a bit more confusing, JavaBeans (the regular kind) are also called out in the J2EE blueprints and other design guidelines as glue between servlets and EJBs, for instance. JSP tag syntax integrates directly to JavaBeans, but not EJBs. In this role they are merely data storage structures, full of setters and getters and typically little else.
Adding even more confusion, or possibly a resolution to the confusion: The later J2EE specifications made the EnterpriseJavaBeans valid JavaBeans.
Perhaps as a result of all this confusion, or perhaps for other reasons, some people think BeansConsideredHarmful.