Even tho I've edited templates manually and with plugins it will still say "There are currently no templates which have been updated since you last upgraded."
Yes, there is a problem, on my side it was only showing a few templates, but not all.
You can manualy check your templates and revert them if neccesary.
I haven't seen any problems from 1.8.1 -> 1.8.2 -> 1.8.3 -> 1.8.4. Also I haven't seen any other issues/reports about this so I guess we can safely reject this.
Rejecting, feel free to comment if you've more information.