We recently integrated Social Connect to our Website (allowing users to register to our website using their Google/LinkedIn accounts).
How do I push their social media information to Marketo? Should I use their API or is there a better way to integrate it to Marketo.
The Social integration Marketo has built in would be for social sharing of your pages, which probably isn't what you're looking for here. Deploy Social on Your site - Marketo Docs - Product Docs .
I'd go with the API route.