Hugh Hefner is out with the old and in with the really, really young.

As various celebrity gossip outlets are reporting, Holly Madison and Kendra Wilkinson have been replaced with Karissa and Kristina Shannon.

While the former pair (along with Bridget Marquardt) helped make The Girls Next Door into a hit reality show, the latter twins are helping to make the Playboy Mansion into some sort of detention center.

But ratings and police records aside, we wanna know if you think Hefner has upgraded or downgraded his girlfriend collection.

Who is hotter: Holly Madison and Kendra Wilkinson or Karissa and Kristina Shannon?