In case anyone missed this article on the http://www.creationkit.com/What%27s_New, it's a great starter for people familiar with older versions of Bethesdas tools.
In particular, I wanted to point out the double right click ability, it's way cool. This works for most dropdown types within forms, and brings up the edit window for that object. Very handy and saves a lot of time.

in SkyrimEditor.ini, bAllowMultipleEditors=0 is default. Setting it to 1 allows you to open multiples if you have the resources for it. This can be handy for testing changes or making mockups for worldbuilding without making unwanted edits to your actual mod.

As with SkyrimCustom.ini, SkyrimEditorCustom.ini can be used, setting here override SkyrimEditor.ini, and won't be overwritten in future updates to the CK.

For newcomers, right clicking on an object in the Object Window, and selecting "Use Info" produces a list of objects or cells that use it. Discovering which FormList(s) an entry is a part of can be helpful, for example.