@Nemo:
Wow, that is pretty impressive for one-handed photos. They look very sleepy.
Out of curiosity, does the front and rear assembly structure change much from this age to when they are typically evaluated at 8-10 wks? Of course they change in size, but could say a seemingly laid back shoulder dramatically change to a straight shoulder over the course of those few weeks?
Photos at this age can only give you a general idea. The pups have only been up on their feet for a few days and they have not developed the muscle tone to enable them to stand fully erect. What you see now may very well change once the pups are able to stack. Once they reach about 8 weeks they usually become WYSIWYG. (What you see is what you get.) There are no guarantees though. Bones and muscles continue to lengthen as the puppy matures and there can be changes, especially if the litter is outcrossed. As a general rule, angulation, especially in the rear, will straighten up a bit. If an 8 weeks old puppy is nearly straight front or rear you can almost guarantee it will be straight as an adult.
How do I grade puppies? Grading starts as soon as they are walking. I look for puppies who are coordinated. Puppies that have a front and rear who have the same degree of angulation are almost always the most coordinated. This is because they are balanced. Balanced puppies usually require little effort to stack. (When they aren't energetic anyway.) You sit them down and their feet land in the right places. When they are about 7-8 weeks, I hold them up with two fingers of one hand under the jawbone and a couple of fingers of the other hand coming between the hind legs. (The Pat Hastings method.) When the puppy relaxes you can really see angulation. Puppies are always observed just running around the house or yard too. Most puppies run instead of trot though.
Some of these pups will be shown in conformation, some will be lure coursed and compete in agility, and the rest will be going to pet homes. Temperament and personality of each pup has to also be taken into consideration to match it up to the right home. This is why I do not promise specific puppies to anyone until after they are graded. I have never had a complaint from anyone who has obtained a puppy from me and several have come back for a second pup later on.