Even in current literature on PHP 5 object oriented development, you'll mostly see mentions of the "public static" order. And it isn't strange, I can understand that some people prefer the PPP at the start to give clarity on the access rules for methods.
While looking around inside the symfony code, I first encountered the "static public" order of keywords. At first, I thought this strange, but the more I look at it, the more beautiful I think it is. It gives a great overview of which methods are static and which aren't.
In the end it is of course a personal preference, however I've found my preference shifting towards the latter over the past months. I decided to check which was preferred most in my twitterverse, and here's the results:
As you can see, a big majority still prefers "public static". However, even more important I think is that the "static public" had more ground than I expected (or perhaps it's that a lot of people that follow me come from the symfony world). Having 2 votes for the option "I don't use static methods" was perhaps also a small surprise, but I guess it depends a lot on what you work on as well.
If you haven't voted yet, feel free to give your opinion in my poll.