Robin Pierson picked up the baton where Duncan left things in 476 AD and is continuing the story of the Roman Empire - the eastern part, anyway) at The History Of Byzantium. He's up to the First Crusade now. One thing that I particularly like is that he has summary episodes at the end of every 100 years or so.
Dwight (you do read him every day, don't you?) left a comment pointing to Mike Duncan's excellent The History Of Rome podcast. It is breezier than The Fall Of Rome (especially after the first 10 or 15 episodes) but takes you from the founding of the Eternal City to the last Emperor in the west. Duncan's current podcast is Revolutions which covers the great revolutions of modern times, starting with the English Civil War of the 1600s and the American Revolution of the 1700s. His humor is there just like in The History Of Rome, but in a modern era. Recommended.