What are the ups and downs of using FastCGI C++  vs.  PHP/Python/Perl to do the same job. 
Any performance or design pitfalls or using one over the other? Even your opinions are welcome. (Tell me why one or the other rocks, or one or the other sucks).
Using C++ is likely to result in a radically faster application than PHP, Perl or Python and somewhat faster than C# or Java - unless it spends most of its time waiting for the DB, in which case there won't be a difference. This is actually the most common case.
On the other hand, due to the reasons benhoyt mentioned, developing a web app in C++ will take longer and will be harder to maintain. Furthermore, it's far more likely to contain serious security holes (nowadys everyone worries most about SQL injection and XSS - but if they were writing their webapps in C++ it would be buffer overflows and it would be their entire networks getting p0wned rather than just the data).
And that's why almost nobody writes web apps in C++ these days.
FastCGI C++ vs. A Script Language (PHP/Python/Perl)