There are no recent pre-compiled packages available, so the source way is the way to go, for now.
OpenMW, an OGRE-based engine for TES3's game data, is now 0.5-versioned. Considering that the project started in this year's june, this number is quite impressive! Does this mean that we will have a final version of OpenMW by the start of 2009's summer? :D
However, animations, interaction and user interface are not yet implemented. Also: check out these videos that show the progress of the engine so far.