There are petites that have a short torso and long legs, thus not all petites wear petite jeans in length, some of us wear regular or even longs. Also petite and thin doesn't mean small breasted, just the opposite. I wore a 32D in 6th grade and I was 105 lbs. I'm older now and larger breasted even though I'm still 105 lbs. Petites can have small band sizes and be large cup sizes. I have a forum for busty girls/women with small bandsizes:

http://community.livejournal.com/thirty_twod/profile

Petite means height, but there are small, medium and large framed petites. Most articles I read on petites are for one type only- short legs and long torso and it's assumed smaller breasted. Petites are built differently not just height but body type and size.