Would you care to explain why you disagree?
I don't think the parts you highlighted in the quote are incorrect in any way.
Ruby is getting more and more popularity as a choice for creating web applications. PHP is indeed designed for web programming, do you see it used anywhere else? Besides, PHP was started as Hypertext Preprocessor. Javascript/jQuery on websites is also very important for a decent user experience. And for the Facebook apps, as far as I remember, they are simple web applications, the only thing you may have to learn is to use the APIs provided by Facebook.
I'm willing to bet that I was one of the very few that was around on the net during the PHP explosion, so I'm going to take it directly from the PHP homepage:
http://php.net/manual/en/history.php.php
PHP as it's known today is actually the successor to a product named PHP/FI. Created in 1994 by Rasmus Lerdorf, the very first incarnation of PHP was a simple set of Common Gateway Interface (CGI) binaries written in the C programming language. Originally used for tracking visits to his online resume, he named the suite of scripts "Personal Home Page Tools," more frequently referenced as "PHP Tools."
A quick look up on the definition of CGI:
Common Gateway Interface (CGI) is a standard method for web server software to delegate the generation of web content to executable files. Such files are known as CGI scripts or simply CGIs; they are usually written in a scripting language.
So, taking from these two texts you can see that your statement that:
PHP is indeed designed for web programming, do you see it used anywhere else? Besides, PHP was started as Hypertext Preprocessor.
Is indeed incorrect. PHP was designed to be a common interface between the end user, and the web-server creating dynamic content possible; such as in the example of Rasmus using CGI binaries used to keep track of visitors, and as we all know, C is not a web programming language. Just as a note, I use PHP for many console applications in relation to server management that have absolutely nothing to do with web programming. I simply like to use PHP because Bash is a bit heavy-weight for some tasks when compared to PHP.
There are some other languages like Python or Ruby which are common to code web applications.
While web programming with Python and CGI is prevalent, you do not code for the web using Ruby, you code for the web using Ruby on Rails which is a web framework that has been written in the Ruby programming language. A VERY slight difference, but a difference none the less.
To illustrate my point:
PHP:
if($ruby == $rails) {
echo $ruby.' is equal to '.$rails;
} else {
echo 'I think we can all agree that '.$ruby.' is in fact not equal to '.$rails;
}
In the today WWW you'll need Javascript for sure. Javascript is also used to control a Flash app with your site.
Javascript is indeed extremely useful, especially when dealing with web applications, however it's not "necessary" as you've misleadingly led the reader to believe. Just as a point of fact, Javascript is not used to "control" Flash applications; instead Flash (SWF) needs to expose functions which are interpretable via Javascript using an ExternalInterface API allowing Javascript to "call into" Flash and vice-versa, but not to control Flash.
Finally:
Facebook games are simple web applications. They can be written in the same languages like all web apps.
While Facebook 'applications' as they're called are indeed applications written for the web, I hardly think companies such as Zynga would agree with you that they've built a 'simple web application' such as Farmville.
I can understand that many of you might disagree with my analysis believe that I'm just trying to split hairs; however, I was simply trying to answer in earnest. We're all programmers, and we all know the value of 100% correct information.