I know this makes me a heretic, but the whole shape/size guessing game has me sort of hesitant to start a new pair of dry jeans (I was really close to pulling the trigger on some stuff at big soho). As you all have said, over the long run both washed and dry jeans will change in shape, but I feel like you're always gambling in some sense with the latter.
We see the same posts about tons of different labels/cuts: do they shrink, do they stretch, how much, etc. etc. LA Guy's post re: yarn types made me think that it's totally a moving target anyway. This is kind of crazy, b/c aren't you dropping like $200+ on jeans that could look kind of wack on you after a few months/washes?
And then there's this wrench thrown into the equation, from History Preservation's Canes description: "due to the sometimes-erratic characteristics inherently associated with the raw, heavy cotton turned into denim produced on the old shuttle looms, waist measure can fluctuate by about 1" smaller than the label on the dungarees states". And don't even get me started on shrink-to-fit; I'm way too dumb to figure that out.
haha. this thought process along with me freaking out to my wife at ikea yesterday because EVERYONE was wearing jeans has led to my new promise to myself to only wear trousers.