Mambo has emerged as one of the best CMS of the decades. What Miro and the Mmabo team did for the last few years was really wonderful. The decision that Miro and his crony took to commercialized Mambo did not receive a warm welcome from many Mambo core freelance developers. Therefore they split from Mambo and form Joomla. 

Joomla want to remain as solely 100% opensource script that can be used,designed,altered and modified by everybody. 

As a pioneer in users oriented CMS, Mambo has gained a very wide reputation. The stability of the script and the progress of the development, do improve day by day. Hence the new emerging Joomla and the former team members of Mambo is on their way to overtake Joomla.

So what is the different between Mambo and Joomla?

In my humble opinion, prior to recent situation and scenario, Joomla is leading the rivality due to the mass migration of former Mambo developers and team members. As opensource did matters, resource of various modules and components of Joomla are easier to find compare to Mambo. And the simplity and design of Joomla components and modules are up to date and contemporary. Eyecatchy!

Mambo is like old papa rite now. The components and modules are almost out to date. They have being abandoned by their former developers. Famous developers like Athur Konze, Mambosolution, Mamboschack etc etc, are now switching themselves to develope Joomla components and modules. 

So all this things might influence my decision to switch from Mambo and Joomla. I have been using Mambo for almost one year now for my Biofuel Projekt.