Jonathan Sachs wrote:
<snip>
>
> Speaking technically, it seems to me that PHP is likely to be a poor
> choice for large-scale services where hundreds or thousands of users
> will be hitting the web site at the same time. I'm guessing, though,
> and I wouldn't know how to judge how large is too large. Perhaps
> there are other areas where PHP is particularly weak or strong, which
> I do not yet know enough to wonder about. Hence, my question.

I am not sure about the back-end, but at the front end, Facebook uses
Php and JS. Signing in takes you to the page below. Facebook's
popularity can be judged at Alexa.

http://www.facebook.com/home.php?

http://www.alexa.com/data/details/tr...s/facebook.com