Nope. I know all of the launchers I've installed and tried. Besides, these two launchers are not from the Android Market. One is pure Google Android, and the other is Motorola Blur. Both, AFAIK, predate the upgrade to ICS and I can only surmise that, since they both look and act the same, the Moto Blur was supposed to be the stock Gingerbread launcher under Moto/Verizon, and, somehow, the underlying google/android launcher was also installed when the phone was first set up last December. Both appear, on low-level investigation, to have been there when I first got the phone.
"You're traveling through another dimension, a dimension not only of sight and sound but of mind; a journey into a wondrous land whose boundaries are that of imagination. That's the signpost up ahead—your next stop, the Motorola Zone."