PHP makes it possible for people to use it poorly, yes. Blame bad developers, not the language that lets them write bad code.

If I want to write a widget that a majority of designers can easily plug into their own sites, I write it in PHP, because it's portable.

Maybe that makes me an amateur, but sometimes I can't just code in the pretty, pure languages all day.

I agree PHP has a lot of ugliness to it, but it's hard to argue with things like the success of Facebook.

If that's not serious webapp development work, I'm not sure what qualifies.