I also vistited joomla site to many times
joomla.org/
And i think, before a week with contact with joomla, is to easier building websites with joomla 1.0 or 1.5 !! lool
The main diference is that the joomla 1.5 is most organized, modular, and the backend is more atractive ... !!
But, in a level of the documentation for developers to joomla, is very poor ... !!
It dont have a complete guide / reference to developers, and the documentation are so dispersed in the internet.
If all documentation are concented in a reference, book, ..., it has very,very better to developpers ... !! looool
Joomla 1.5 develloper guides are better, but joomla 1.0 developer guide are so poor ... !!