First off I quote from the article:
One line in particular is very important, so read closely—it says, "At the start of your turn, REMOVE attached ally and all opposing allies FROM THE GAME." I'm sure that all of you have seen the Death Rattle keyword by now, and obviously you’ve understood just how powerful it is. This card gets around Death Rattle nicely, as the allies are removed rather than destroyed. Of course, what makes this card so great is that the effect is completely one-sided! You don't have to worry about killing your own dudes in conjunction with using this little gem.
The highlighted text refers to allies with Death Rattle (only one of which we have seen). This is a highly speculative statement that only applies if there are multiple playable allies with Death Rattle.
Now onto playability...potentially huge...I think that it may replace my Suspended Curses, since for one more it becomes a board wipe. (I understand that Suspendeds target more things, however I tend to Banish to the Nether those and slap Suspendeds on allies lately).