It's not silly to be thinking about it! Our bodies do such crazy things throughout pregnancy, it's impossible not to think about it.
I did a lot of googling post-pregnancy bellies myself just to see what the range of difference was between women.
http://theshapeofamother.com/ This is a great site dedicated to real women sending in pics of themselves. Like everything, it all depends on the individual.
Since you have lost so much weight you probably already have an idea of how much elasticity your skin has.
A lot of women say they leave the hospital looking about 4-5 months preggers, and after that they get a 'deflated balloon' look for awhile. Maternity clothes or yoga pants are still your best friends. Besides, it`s all about being comfy at that point.
Immediately after giving birth your uterus will still be fairly large, it'll shrink rapidly (more rapidly if you are nursing). Once your uterus is sitting back in your pelvis (about two weeks) the loose skin and lax transverse abdominal muscles (your inner girdle) are what keeps your belly jiggly.
How quick it tightens back up has to do with how elastic your skin is, how tight your transverse abdominal muscles were pre-pregnancy, and if you concentrate on exercises to tighten them back up. If you do have the energy/inclination to do exercises to try and get a slimmer midsection after baby make sure you are doing ones specifically for your transverse abdominal muscles (no crunches!)
The old saying `9 months to gain it, 9 months to lose it`applies.
Personally with my first pregnancy I didn't pay much attention. With this second one I believe that because a) I had already been larger due to weight and b)my belly had already expanded due to my first pregnancy it was easier for my stomach to adjust after. I also know I'm fortunate, by a week postpartum I was in my pre-pregnancy jeans.
I'm almost 2 months pp right now and I have a bit of a loose stomach and some jigglyness still, but that's only when I compare it to how my stomach looked before when I was exercising a lot. Compared to what I looked like at my highest weight it looks great! lol
I always seem to write a book's worth in my responses to you! I spent a lot of time wondering about similar things a few months ago and am so glad to pass on as much information as I can that I can't stop typing.