Not a huge difference, but a very noticeable one in-game.
The leveling changes vary from skill to skill, but on average are lowered by about 30%-45% each. The skills themselves increase in level much slower than before, so you feel as if you earned it, and didn't just grind it to 100 in a matter of minutes. Nearly every perk in every perk tree has been altered in some way, and there are more than a few new perks. Version 2.2 is now up! Aegis fixed (again, and properly this time, I promise) for those experiencing problems with the values not showing up in the UI.