Warning Message under Comment Box

In short, don't worry about it

Basically, Facebook scans your pages to make sure their legit (not spam, porn, malicious, etc). When you first add Facebook widgets to your site, they haven't had enough time to scan the pages. Once they do, that message will go away.

I just checked the link you posted, and the message isn't there.. so you're probably already cleared in Facebook's eyes.

Hope that helps,
Alex

I'd still say give it some time. Facebook just puts that message up when it's unsure about pages. The link it refers to is definitely reachable. Additionally, if you click on it in the warning, you'll be brought to Facebook's URL Debug Tool which gives the information it 'sees' about the page:
developers.facebook.com/tools/debug/og/o...ut-us%26Itemid%3D120

While there are some warnings, none of them are critical. Everything in the debug tool says that the URL is valid and that Facebook is able to retrieve the Open Graph data from the page, so you should be good to go.. once Facebook propagates the information from your page to all it's servers. That can take anywhere from 1-7 days, in all honesty. Should it still be there in a few days, definitely let us know, and we'll have a second look.

Thanks,
Alex