Jeremy at Lightspeed Venture Partners wrote about the top social networks for engagement.
You can see the significant activity that make the big guys valuable. There also are some surprises with less popular smaller sites - the point is that they are regularly used and are good advertising buys... a smaller but more involved audience.
I have been having more conversations lately about the real value of "Engagement" - Your most important customer is the one that interacts more effectively with the (advertising) brand - increasing value - building memories. Such as: commenting, sharing, up/downloading... participating!
Join us in discussion about how your customers could or are already interacting with your company. Only then can you develop the interactive mechanisms to nurture and take advantage of this.