Alraiis said:"Dexterity modifier damage" is clear and straightforward only if it means what it used to in 3.5. Looking at stat blocks, however, seems to suggest very strongly that the modifier itself scales with level, which means the damage does as well.
Actually, it's highly unlikely that the ability score modifier is directly scaled and far more likely that you simply get a bonus equal to 1/2 your level on certain rolls. Whether one of those rolls is damage for PCs remains to be seen, but unless you're suggesting that a 30th level rogue can trick someone into "stumbling" over 100 feet, or a fighter can throw down 20 extra damage without making an attack roll every round, I don't think you can say the stat modifier scales with level.