Indeed, the two do not work hand-in-hand with each other. In fact, Source.Python started off as EventScripts3, a complete re-write of the plugin.
In its current state, there are a few things you can already do with SP. It is still in Alpha, so there are still lots of things you cannot do. A few months back, we decided to do a complete re-write on the C++ side to make the plugin more maintainable in the future. Many things that used to be possible have not been added back in. All of the functionality available from the C++ side, I believe is now documented in the Wiki. The Python wiki has many functionalities that used to work, but need to either be rewritten for the C++ re-write or have not been added back in on the C++ side.
In case you have not noticed the wiki (the link is along the top bar of the site):
http://www.sourcepython.com/forumdisplay.php?37-Source-Python-WikiThe Source Modules are the modules that are provided on the C++ side and exposed to us by Boost Python. The Python Modules is the Python side API which can be used to make your life a little easier on the scripting side.
If you have any specific questions, please feel free to ask away. If you notice any issues, please use the Issue Tracker to report them. Though, as this is in Alpha, many issues are already known internally.
*Edit: also, now that L'In20Cible has fixed compile issues on the OrangeBox-engine version, I plan on uploading the newest build sometime tonight (after I get the chance to build on Linux).
Satoon