Starting the client today I was met with the following:

The Launcher is optimizing your World of Warcraft install. This is a process we run from time to time to improve game performance and reduce the size of the install on your hard drive.

The entire process will take approximately 15 minutes under normal conditions. Please do not close the Launcher or run World of Warcraft during this time.

Thank you for your patience!

After this the operation started (on my SSD system it took just 2-3 minute, but that is beside the point) with no option to abort or skip the operation this time.

Please, if the launcher wants to do something that is possibly that time consuming, give the option to skip it if you do not have the time to wait for it.

Same goes for the annoying "doing some non-vital final adjustments" or something, this takes several minutes and if you start to play during it the game install will be broken. It could possibly be that those "non-essential" things that breaks the install is the optimization that is now possibly holding the computer for 15 minutes when all you wanted to do was pop in anc scan the AH in five.