Yesterday, Autodesk announced Revit LT!
Check out the full features page.
I havent had a look at this yet, but I can see potential problems for medium to large users of Revit LT 2013 based on the omission of Worksharing, exports, In-Place Modelling and the API tools. I personally see this version being too restrictive even for the small or occasional user of Revit based on the current features.
Also not sure if you can author family files in Revit LT2013
Here is a quick comparison
Thanks to LawrenceH from Revit Structure Blog