Hi Leonardo,
I believe the plan is to eventually migrate all wikipedias over to the PHP script. So your perspective and help from your side is very much welcome.
You can read about the features of the new script at http://wikipedia.com/wiki/wikipedia:PHP_script and you can browse the current code at http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/wikipedia/phpwiki/fpw/
To download the code, it's best to use anonymous CVS, explained on the PHP_script page mentioned above.
Have fun, Axel
wikitech-l@lists.wikimedia.org