We've got two boys from the same litter and one has a long nose and the other a short one. One looks just like his mom and the other just like his dad. Here are some pictures of them at 6 weeks, 12 weeks, and fully grown. We could tell the difference when we picked them out at 6 weeks, but it became quite a bit easier to tell in the following weeks, so you shouldn't have any trouble with picking a short snout at 10 weeks or so.
One thing I would warn you about - the shorter snout dogs can be more prone to respiratory ailments. We had some trouble with both of them developing some sort of kennel cough like sickness shortly after we got them, and the vet said it would take the short snouted one a lot longer to get over it just due to the shape of his nose (and it did - about a month longer). Just something to be aware of. But I agree - the short noses are pretty cute!
The first picture is the short nose dog at 6 weeks.
The second picture is the long nose dog at 6 weeks.
The third picture is taken at 12 weeks, the one on the left has the long nose.
In the last picture, the one on the left has the short nose.
Hope that helps a little.