I visited Modena on February 23 and 24, 2012 and guess what?
The outside of the cathedral is still covered with scaffolding.
The inside, however, is quite impressive, with its high altar and the variety of sculptures, columns, and brickwork. Unlike many churches in the area, it has been spared most of the "updating" from style to style over the years so even the neophyte art historian can get a sense of the Romanesque style without the distraction of Renaissance, Baroque and modern "add-ons"
The city itself has a small historical district which is pleasant enough but pales in comparison to the porticos of Bologna and the streets of Parma. However, do plan to have at least one meal here--the food is some of the best in Emilia-Romagna.