At my last org we managed to incorporate Marketo forms on our Facebook page for content downloads (without the publish to Facebook functionality of the social suite). It worked well, but took some dev time as Facebook tends to wreck havoc on Marketo's tracking and validation. I believe the social suite accomplishes it with iframes, which could be a lot cleaner, I just don't know how easy it is to build something like that on your own.
We currently have the social suite at my new company, but I haven't messed around with it much beyond the social buttons with analytics. It seems like a slick integration (and I think the social interface is a hint at what's to come with UI overhaul for the rest of Marketo), but the industry I'm in has very poor social media adoption, so it's hard to really find ways to utilize the tools to their full potential.