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Well, I'm not picking on SparkCon - it looks like a fantastic set of events - but increasingly I'm feeling less and less tolerant of those kinds of fit-and-finish flaws showing up when I'm interacting with a Web site.
Imagine what you would feel like if you were meeting a new business associate to chat at a cafe, and while you were talking they said "hold on...", unzipped, reached inside their undergarments to adjust themselves, scratched around for a while, and then tried to resume with "ok, go ahead".
We are all human, but some people are just more circumspect than others. That's why, intuitively, PHP rubs me the wrong way: inelegance.
Update: I'll give two examples. First, PHP's over-reliance on special characters and strings of special characters as operators in the syntax (from its Bourne shell -> ED/AWK/SED -> Perl heritage); and second, its concomitant reliance on gruesomely ugly idiomatic expressions for expressing trivial relations and operations. Neither of these PHP characteristics adds value to the solutions; both detract considerably from the readability of the code and add excessively to its code length. Since code-length is a correlate of error injection rate, PHP is objectively a worse basis for making an investment in code.
See also this tongue-in-cheek comparison.