MTO EXCLUSIVE PICS: Kim Kardashain Shows Off Her New 'SURGICALLY REDUCED BOOTY' . . . In A THONG BIKINI!! (Do You Like The OLD BUTT . . . Or NEW??)

Original: broke the news a few weeks ago that Kim Kardashian was undergoing plastic surgery - and getting her butt reduced.

Well check out the result of the surgery - her new butt is MUCH smaller.

We're not ready to CHOOSE which booty we prefer. But we're leaning towards the old one . . .