Facebook experienced a glitch late on Thursday, which took down a whole lot of sites temporarily, illustrating just how much power Facebook holds over the web.

Users would visit a site, and then it would redirect to an error message on Facebook.com.

Sites affected by the bug include: Hulu, CNN, MNSBC, Gawker Media sites, ESPN, Reuters, Yelp, Business Insider, Soundcloud and the Washington Post, to name a few.

The statement Facebook has been sending around to various publications is:

“For a short period of time, there was a bug that redirected people logging in with Facebook from third-party sites to Facebook.com. The issue was quickly resolved, and Login with Facebook is now working as usual.”

All Things D has video clip showing the bug in action:

The bug didn’t last long, and might not seem like that big of a deal to some, but when businesses all over the web have sites that are connected to Facebook, it’s a big deal to know that their sites (and potentially transactions/conversions) can be compromised simply because Facebook experienced some problem.

Really, even though it was Facebook this time, who’s to say it couldn’t happen because of any other service that millions of sites are connected to in one way or another, like Google or Twitter? Twitter is practically famous for having site issues, though I don’t recall anything of this nature in the past.

It’s unclear how many sites on the web are actually connected to Facebook. This isn’t one of the stats that Facebook displays in its stats section. Back in June, Pingdom reported that 24.3% of the top 10,000 websites in the world have some form of official Facebook integration on their homepage. Frankly, I’m surprised that number isn’t higher, though it may very well be by now anyway.

Still, these services have become important components of how a large portion of the web operates – how businesses operate. For many, simply disconnecting from them is not an option, and they are left to the mercy of these higher Internet powers.

It is Facebook’s massive reach across the web that may soon prove to be a hugely powerful weapon in the search space. As you may know, Facebook recently unveiled its new Graph Search tool in beta. It’s still rolling out, and Facebook is working to bring many more features to it. During the announcement, Mark Zuckerberg indicated that Facebook’s Open Graph would be added in the future. One has to imagine that Facebook-related activity (which could be any number of things as long as people are logged in) on sites across the web will be part of the equation, which could actually play a major role in ranking content.