Automatic posting and reposting to Facebook and Twitter.
You need the Pro version. All you have to do is buy a key.
SharePress' features are without parallel. Being able to post automatically to your Facebook page is only the beginning. The reposting feature is the one that has the potential to bring the most traffic growth to your site.
Plus, Facebook is a very difficult platform the work with - their motto is, "Move fast and break things." No joke. When you pay for SharePress you are paying for Fat Panda to constantly monitor and maintain this stable connection between your site and the social Web.
No. SharePress Pro provides you with the ability to customize message (status update) and the photo that appears on Facebook. Posting via Twitter does not provide this feature.
Soon. SharePress 3.0 is nigh.
At this time it is not possible to publish to Google+ as Google does not offer a writable API.
Other services and plugins support writing to Google+, but they do this by storing your Google account username and password, which is extremely dangerous.
Documentation and support for SharePress are available here.
E-mail based tech support is available to Pro customers. All you have to do is buy a key.