Everyone working with PHP is probably asked quite often what the difference is between PHP and Java (or C#/.Net). Besides the usual aspects: scripting vs. compiled and in-process vs. seperate process and Multithreading etc., i think there are some "soft facts" that might be even more important for commercial software development.
For example: In Java (or C#) you can code any architecture for any Problem. Some will need more development time and more hardware, others less. In PHP you still have a lot of ways to solve a problem but not as many as in other languages because of the limits to object lifetime. Some of the possible solutions will lead to a dead-end road in terms of performance and maintainability. Therefore, intelligent PHP developers tend to communicate first. They search for proven solutions, maybe existing PHP-Extensions and working code before defining an architecture (and i dont mean Design Patterns, but examples of working solutions). Maybe it even helps in this case that quite some PHP developers don't have a solid computer science background and therefore they need this kind of inspiration to find a solution at all. On the other side, people tend to be proud if they have something working in PHP thus blog about it and opensource their architecture and code.
Of course you find all this also in Java or C#, but much much more in the PHP area. It seems like the "Not-Invented-Here" syndrome is less mighty here or people are more motivated to share.
Anyway, the result is: Even though there are not so many standards in the PHP world, successful developers have a common understanding about the do's and don'ts in PHP. This unwritten standardization leads to a very interesting fact (also shown in the Plat-Forms contest): PHP solutions of different teams (of comparable skill level) are much more consistent than in Java (or probably C# (Prof. Prechelt, please forgive me this un-scientific deduction)). Meaning: PHP appears more predictable than other programming languages. Now this is a fact that the business decision takers might be interested in...
