The developer diary shows that the graphics have indeed gotten a nice overhaul and the controls and menus have been updated to be much more touchscreen friendly. The completely new interfaces and button layouts should make playing a lot more intuitive.
It's wonderful to see how much effort and thought DotEmu have put in to this port. They've been quite thorough, and by the looks of it, I'll be spending many hours hack n' slashing Harpies in ancient Greece again.
Titan Quest arrives on iOS on May 19th (and Android "shortly thereafter")