I just spent a while composing this response as a comment on Marcus Whitney's "Juvenile Demands and Criticism of Open Source Development". Since it turned out quite long, I thought that I'd turn it into a blog entry of my own. Marcus is indirectly referring to someone that I'm going to call Mr. E.
Mr. E seems to have some issues with the PHPSC, and perhaps something of an overlarge ego, both of which are annoying characteristics. However, you need to understand what motivates him. He likes PHP and wants it to be the best, and part of that is keeping its security record in tip-top condition.
When a PHP application is popular and is riddled with holes, PHP itself is tarnished by the reputation of that application. Mr E devotes a lot of his time listening out for news of problems, as well as searching them out and coming up with patches to address them. You can (and probably should) forgive him getting annoyed when he's put out all the effort, often supplying a patch to address the problem, and had no one take any positive action.
While security problems remain unaddressed, in the real world, people are losing money through increased bandwidth costs and system reinstalls--and thats the best case. The worst case is that some sensitive data (credit card numbers, perhaps) is being collected and used illegally. This leads to all kinds of trouble for the victim and the people running the site.
My personal opinion on the responsibilities of OpenSource development is this: it's good, it's free, there's no warranty. If it works for you, that's great. If it breaks, you get to keep the pieces. The author doesn't owe you anything; you get what you pay for. If there are security flaws, so be it; there is nothing that says that the author has to push out a release immediately, nor is there anything that says that they have to handle the matter according to the proper form for disclosure of security problems.
When it comes to popular OpenSource projects, there is usually a decent sized team (eg: more than 1 guy) that looks out for it, fixing bugs, working on new features and so on. Still, they have no legal, binding, responsibility to you, the end user. That's still fine; you're still getting what you paid for.
Here's the differentiation: if the guys behind OpenSource projects behave responsibly, that makes their project into a Great Project.
If they're ignoring security advice and doing nothing about it, that tells you something about the goals of the people developing it. It doesn't necessarily make the project a bad project, it just doesn't make it a Great Project.
So, people installing applications have a choice: they're free to install any app they want, of course, but good sysadmins will generally only want to install Great Projects on their servers. How can they tell if a project is a Great Project or if it's cool sounding project run by people that don't really care about security? If you take a look at the phpBB site, you'd be forgiven for thinking that phpBB sounds like a mature, stable, solid and secure application.
Obviously, you can't trust the marketing material produced by the people that built the project.
So how else can you determine if it is a Great Project ? By reading around and listening to others, that's how.
If nobody spoke out about the security problems of an otherwise Great Project nobody would know about them. And in this regard, our Mr E is doing the right thing--he wants the people behind the project to take action before the problem escalates up to security advisory status and is marked as "vendor took no action". When this happens, the reputation of the PHP project itself also suffers by association.