> There are existing products that perform similar roles to this system, including MogileFS (http://www.danga.com/mogilefs/), which implements server and client component software and uses an HTTP interface.

Not only is one sentence way too little to base an entire article on, but it didn't even merit a reference in the book's index. Another admin objected "Books results yield only trivial mentions" and it looks to me like he was right—nobody managed to find a verifiable article or book section by a disinterested third party that said anything at length about MogileFS. Wikipedia is not about "if the press mentions the product at all, we can start writing whatever we want about it." Wikipedia is about "show secondary sources for what you write" but instead proponents tried to handwave and argue their way past some "kid" who made the right call.

As for those other systems, well, GlusterFS looks similarly obscure and unsourced and probably also isn't ready for its own article. However, Usenix gave Ceph eleven pages in ;login: which pretty much anchors its notoriety in the industry.