This is a good update and is explained in detail in the developers blog.
This update is aimed at new runescape players who just create an account. As we know when you are level 3 you hit a lot of zeros. Now instead of hitting 0, level 3's might hit a 9 or so which would = 0.9 with the old system.
This means considerably faster training for lower levels and consistently higher xp for higher levels as well now since you can basically hit XX.X instead of just a whole number.
So in my view this is not a fail update and people should stop flaming every update jagex makes. Yes I agree that it is dumb they changed the name but as a whole this update is pretty good for everyone.