Creepers no longer walk while you are in their radius rate. Like, if you stay AFK, and a creeper approaches, it will just stay at the farthest possible range and then explode, instead of coming as close as possible and then explode. This causes alot less damage. It would only be able to kill you if you would be injured already, and so far there likely is no "mining when suddenly sssh BOOM. Death.", as you likely would have full health when mining.