We have been working on an Open Source CRM application that is written in PHP utilizing Yii, JQuery, and RedBeanPHP and relies heavily on test driven development. It might be one of the most complex projects on Yii to date. Right now, we have 1000+ unit tests running across eight server configurations and utilize selenium for a nice set of functional tests too. Take a look and let me know what you think: http://zurmo.org
We chose RedBeanPHP because we thought it was a better fit for our project and offered some additional flexibility we liked. For ORM, RedBean auto builds database schema and keeps in sync with definitions in the application.
We currently have functional tests developed for IE, Firefox and Chrome, and that is why we currently support only those browsers in app. However, it is possible that application works fully in Opera too, and if you want to try how it works in Opera you need to add Opera signature to BeginRequestBehavior::handleBrowserCheck() function(app/protected/modules/zurmo/components/BeginRequestBehavior.php).
What I found out is that most people use SugarCRM and Salesforce because of their MS Outlook Plug-ins and contact/task auto sync features so I guess you guys probably have a plan for developing MS Outlook plugins too
You might also want to be looking at developing a sync tool for Google App powered emails