I haven't followed PHP closely throughout its history, but I think at least some of the hate comes from questionable features that used to be a problem, like ma

I haven't followed PHP closely throughout its history, but I think at least some of the hate comes from questionable features that used to be a problem, like magic quotes or register globals (and the underlying problem that PHP would let you write code without knowing what you're doing, and thus ending up with horribly insecure web code). I think a lot of that has been fixed, but the perception lingers. Another reason to dislike it is that it occupies a somewhat awkward niche in the language spectrum. It's not as strict as something like Java, which can make it more difficult to use for large projects. It's not as powerful or expressive as something like JavaScript or Ruby/Python, which makes it a lot less fun to use. The only thing PHP really has going for it is that it's the closest you can get to a language that allows you to just write code that works "on the web", without having to fiddle with any server configuration or install anything (and it has a good set of libraries well-suited to this purpose).