Just started "The Dainty Sload" quest for the thieves guild. It tells me to go speak to Erikur in Solitude, On the map it says that he's in the middle of the river just north of Solitude, I went to his house and he's not there, when I search the river looking for him I can't find him, Does anyone know if they're going to patch this or if there is any fix for this? (playing on xbox 360)

Have you tried just waiting? I was in the DB sanctuary on the last real DB storyline quest, and I looked everywhere for Nazir but he wasn't anywhere to be seen, waited and he appeared, seems he just didn't load.

I didn't have any trouble with it. He moves around though. Goes home at night and sleeps, and I think he goes to the Blue Palace during the day.