Well, this is not closer to PHP IMHO :) This short syntax is depreciated (or if not, than it is not supposed to be used anymore), and resembles an XML processing instruction instead, which is a bit more general, than what we would like to express here, don't you think?
You're right ;)
I think I found the bad thing in the current favicon, the letters height is too big.
Maybe ;)
What about this ones :
[1] http://didou2.keliglia.com/favicon.html (1 px removed from the bottom of the two p and the top of the h)
[2] http://didou.keliglia.com/favicon.html (like [1] but 2px removed from the h)
[3] http://didou3.keliglia.com/favicon.html (like [2] but replacing white by gray)
[3] is the one the closest to the PHP Logo IMHO.
I would prefer a lighter logo, but you are right that the PHP logo is not that light, so maybe [3] is the closest. Or [1] outlined with gray instead of white. I have not measured how the height of the different parts of the font relate to each other on the original logo ;)
Goba