Most sites are just app-supported. I know this is sort of a logical progression, but a site specifically for browsing random applications seems a little weird. Is that just me?

Seriously, every web industry has it's galleries, ad websites have been for ages, even ones with banners only http://bannerblog.com.au/

It looks like it's run by Facebook to promote quality campaigns amongst the marketing community. My first thought: "Dribbble for Facebook campaigns"