While maps were always in 3D, previous Etrian Odyssey games had hand drawn monsters art in battle.
Atlus made a change for Etrain Odyssey IV, which replaces sprites with 3D models.
Famitsu confirms F.O.E.s will be in Etrian Odyssey IV. These powerful monsters will be visible on the map so you can figure out how to avoid them. Another interesting tidbit is you get to explore Yggdrasil in a hot air balloon.
Etrian Odyssey IV is slated for release on July 5 in Japan.