Ive seen this on many sites over the past couple of months, and now I have seen it on mashable too. Floating Social is great, but its so in the way down the side with all the different services. Mashable now have this feature where the total is shown, which can be clicked to allow services to share on. The Next Web and many other sites also have this feature. Please find attached screenie.
You should make it an update for the next version of Floating Social, allowing the option to show all services, like it is now, or a single button with the total, like these top sites do.