There are many good articles/ posts/ temperment tests around designed to help you increase the odds of ending up with the type of dog you desire. If you were evaluating a 1 year old instead of a puppy how would your criteria change?

Jeff,
I think that if you are looking at a puppy, the most telling thing is going to be bloodlines. Of course you want a confident puppy, showing the desire to chase toys and take the item in its mouth, but with a young dog there are too many things that can change and you can't test defense. If you are looking at a 1 y/o dog you have a better idea of how the dog will mature. I want a dog that will readily chase and grab prey items, will not startle from loud noises. Also I like the dog to meet a challenge (hard stare) without fear, but without flying off the handle right away. Also, I test resource guarding. If I give the prey item I mentioned earlier to the dog, will he actively try to guard it or at least possess it? If the dog shows all these thing he would be a good candidate. If he's lacking in only one area I can work with him, but if he's weak in more than one or two of these, I'll find another dog. There are many other test a google search can probably turn up a more formal test. This is just something I can do quickly with any dog. Also, do it with the handler and alone. Some dogs will be tough with their pack, but weak when left alone.