Actually jaguar's been using the grille design/shape for quite a number of years before the very notion of the Taurus grille was conceived.
The new XK is a nice looking car, quite disappointed with the interior though, any semblance of Jaguarness have all but disappeared. Even the flawed but characeteristic J-gate is gone. The XK's interior might as well be a Lexus'.
If you are going to cross-shop the awaited E92 M3, wouldn't the upcoming XKR be a more valid comparison?