This is a great addition to busy news orientated sites.
We use Acymailing currently which also automatically converts urls within an email so they can be tracked. We can see who has opened the email, how many times a link has been clicked and how many users have unsubscribed. Are there any plans to add these kinds of features?
Facebook integration would be phenomenal, save pestering users twice. If they're separate then Facebook will have to remain the default (just because everyone uses it, and for sigh-on) shame they couldn't make it look nice. I'm sure it's horribly tricky too!