I visited this WHS in November 2014. I visited both Eisleben and Wittenberg. I decided to sleep over in Wittenberg as there's much more to see and do. Before the 500th anniversary of Reformation in 2017, however, I'd suggest you focus most of your visit in Eisleben. It lacks the tourist groups of Wittenberg and everything is open and without scaffolding. I visited Luther's birth house and the church where Luther was baptised. The interior of the church has been completely restored and given a modern touch with a "jacuzzi-like" baptism font in front of the old one with ripples reflecting on the church's walls. I also visited Luther's death house which is less interesting than his birth house (the info given there is much more structured and interesting). Luther's statue in the middle of Eisleben's square is particularly well made (picture). In Wittenberg, the highlight is the 95 Thesis Door (perfectly visible) and the Schloss Kirche which is undergoing major restoration works till 2017. The Luther museums in Wittenberg I found to be less interesting than those in Eisleben and most are undergoing restoration works too. If you have enough time, I'd recommend visiting Halle and it's huge church. It's well worth a visit.