Liferay 5+

• Liferay experiences thread link
  
• Public render parameter(JSR 286) in liferay to read a request parameter: link 
• Website search (page search based on meta tags : link
  
• Building a hello word portlet using plugins SDK:link
• Liferay and opensso integration:(quite neat) : link
• Organization vs community : link
• Adding validation messages in liferay : link
  
• Popup in liferay : link
• Liferay hook plugins : link : Hooks are event handlers and they are Good stuff !.  Liferay provides the following events : Application Startup Events, Login Events, Service Events                                               Gotchas : Better to use hooks as plugins. Tried in ext once and it broke other hooks.
• Customizing labels(internationalized): Done in Language-ext.properties
  : link
• A good review of liferay 5.x is here
  

• Liferay architecture is SOA based :

* Above image is taken from book Liferay Portal 5.2 Systems Development.pdf