DC Takes Legal Action Against Mark Millar's Nemesis

Back in December, details were revealed about Mark Millar and Steve McNiven's next project at Marvel entitled Nemesis.  The familiar looking new character was described as "What if Batman was the Joker?" and "What if Batman was a total c***?"  The image seen was a combination of Batman and Heath Ledger's Joker.  The question I had was what would DC think about this?
 
Now we know.  Bleeding Cool has reported that DC has taken legal action over the image.  In the March Solicitations for Marvel, a cover image for Nemesis #1 was not available despite the image having already been shown.  Apparently the cover had to be changed and there wasn't time to have it ready for the solicitations.  It's unclear how much of an affect this 'legal move' will have on the overall book.
 
Are you surprised by this move?  Do you think Mark Millar actually thought DC wouldn't have a problem with this image and description or was it part of a publicity stunt?  We'll have to check out the book in March to see if the character's nature remains true to his original description.