I must say WD has not only made the most fundemental of breaches of trust possible for storage media vendor, but they have really droppped the ball in giving any sort of clear guidance and messaging to the community throughout this whole Mavericks debacle. The WD twitter feed has a morbid comical feel to it with nary a mention this ongoing disaster, just a constant stream of mindless happy/smiley marketdroid speak. I would REALLY like to see some sort of live blog to get updates on what is know and what the heck is known and what is being done. The only thing I see are fellow WD customers in agony and WD sort of trying to sweep it under the carpet.
Fortunately I have not upgraded to Mavericks, but do have a couple of questions.
Is it safe to plug a 1TB USB My Passport for Mac into a clean install of Mavericks?
Is it safe to use any Western digital internal laptop hard drives with a clean install of Mavericks?
Or should I just burn everything with a WD logo, and switch to linux and not look back?
There are not only WD drives affected!  Furthermore it is not at all clear, whether the crashes are the result of a poor Apple Mavericks update or incompatible WD software. Apple keeps far more defensive that WD. (My feeling as an Apple lover: Why the **bleep** do all OS X updates after 10.5  fiddle around on proven connections such as printer or scanner drivers - and now with Mavericks the changed something on the setup standard of external drives. Aside from many other unnecessary changes and uncomfortable “simplifications”…).
Internal disks of an iMac are formatted by the Apple manufacturer, regardless of their make (Toshiba, WD, etc)
Additional WD disks on a Mac Desktop do not require WD software and are probably safe.
I had a Buffalo Drive and a WD passport - initiated with Apple Disk Utilities - on the same thunderbolt daisy chain, when the two My Book Duo archive drives (RAID1) crashed, i.e., became “unraided”. The WD Passport, however, remaind OK. The RAID status of the MyBook Duos were set up by WD Disk Utilities.
A friend of mine has a number of WD MyBook Duo (FW800 and TB) connected to his iMac. The external drives were all initiated or formatted by Apple Disk Utilities, not WD software! So far no problem, but just to be on the safe side, he disconnected now the drives, when they are not used. That is what I shall do in the future anyway to minimize RAID or Disk failures. My crash happened during an iMac lockup caused by iTunes.