This is a follow-up to my earlier article "DON'T Install the new ColdFusion Updater 3".
Update 4 is now out (accompanying blog post from Adobe).
I was gonna say "DO install the new ColdFusion Updater 4", but... do you know what? Unless there's something really important you need in it, my advice would be to wait for other people to install it first, and see how they go.
Maybe install it on Monday.
And, for goodness sake: take a back-up first, create a CAR file of your settings, sacrifice small animals to your deity of choice, and make sure the planets are aligned in a pleasing way before you do it. And test test test before you apply it to any live environment.
Best of luck.