David Welton has some interesting things to say about Scalable Systems.

I disagree that PHP is especially accessible. I mean, a lot of people say they find it accessible, and who am I to argue. But accessible is surely a relative term, and I don’t see how PHP is more accessible than Python, or Ruby, or even (if we keep schtum about monads and suchlike and just present the user with a neat little HaXml-like combinator library for making web pages) Haskell. To what extent does PHP obey the principle of least surprise? The number of confused newbie posts on the PHP mailing list I’ve recently joined suggest that it surprises new users early and often, like a host who flings open his doors to all and sundry but has a hallway rug full of nasty kinks and bumps (with a bear trap at the entrance to the lounge (which is full of broken bottles)). I wouldn’t say that PHP is worse than other languages in this regard; just not particularly better either.