Hi there,
You're very welcome - one of our goals is to keep our users always front-and-center, and to make things work best for the user. So I'm really glad you're having a good experience!
We've been having a few reports of the "Share" numbers disappearing. When we chased it down, it turns out that the services (Facebook and Twitter) return those numbers to us; we don't generate them. So they will sometimes be working on things behind the scenes on their end, and the result is share numbers flux or disappear for our users. There doesn't appear to be anything we can do about it, either. I'm terribly sorry!
Once the service clears their end, they should start re-appearing.
I wish I had a better answer for you, but since it's a third-party service, we just don't have that control.