I would honestly think that 90% of people would choose to not change their last name in this scenari

TurtlesAllTheWayDown

http://www.nypost.com/p/pagesix/laurens_in_love_sQqA6ammonQ0i720loClyL#ixzz1UaS5C52Y

CN: Lauren Bush (neice of W, granddaughter of George HW Bush), once a party girl, is now marrying David Lauren, son of Ralph Lauren.

Direct quote from the article:

The bride will take the name "Lauren Bush Lauren."

I kid you not.