Clarification of commons functionality

I have installed the latest commons distribution at two sites and have joined the http://commons.acquia.com/ site. I am not sure if I am seeing the complete function. I have no trouble installing and configuring the sites and have been, to some degree, able to provide a different theme to one of them. Good work Acquia.

What I am asking here is about the "out of the box" function. What I see is an ability to create groups and join groups post to those groups and to be able to see at the stream page filtered postings based on the groups you have joined. There are many other areas I see but have not tested such as the linkedin facebook and twitter account interfaces.

The question: "Is there a list of features and optional module activations that aid in shortening the learning curve of the distribution as is?"

Our interest in this type of community site is to provide a rich environment for staff, volunteers, directors and clients of a not for profit. Things such as ad-hoc group chats, document sharing (perhaps interfaced to the Google docs platform) and desktop sharing (for demonstration and instruction). I am sure these are more advanced than the scope of the current commons project but 'where to go from here' might be asked for future iterations of the project.

We have found some PostgreSQL issues and will be correcting those in the weeks to come. Of course they will be posted back to the individual modules they represent. On a side note, is there need to also inform this distribution team of those posts?