In my opinion it doesn't matter what a jumper looks like (obviously omitting major conformation flaws). It's all about their athletic ability. If they can jump anything from anywhere and be safe while doing it then in my opinion they are great jumpers.
Hunters is a bit different. It is much more subjective. Conformation means a bit more here. Generally speaking a good hunter is very sane. They give the appearance that anyone, even a beginner (I know beginners don't jump, but I'm just trying to convey the fact that they appear easy to ride), could take them out and jump a course on them. Their gaits appear flawless and flowing. Rhythm in the gaits does not change. Hunters float across the ground. Their movement should be flat kneed and the term daisy plucker is often used. When they jump their knees are square, ears are forward, neck is rounded and down, not in the air and flat.
This is how I see hunters vs. jumpers.
"Be the change you want to see in the world."
A daisy cutter (I'm assuming we're talking about the same thing) is a horse that just kind of reaches and flicks his toes with every trot step. Most winning hunters are more or less 'daisy cutters'.
And they aren't necessarily packers, it's just the rider's job to make it LOOK like they're packers. A lot of them are in fact complicated rides.
While hunters have to jump beautifully, jumpers have to jump effectively. Most jumpers still have conventional form simply because it is the most efficient and safe, but small differences that would count in the hunter ring (like one knee higher than the other or neck not exactly reaching down to balance) don't count.
Hunter conformation tends to "appear" more downhill that your typical dressage or jumper. A nice topline is essential. You want all the qualities that make horses good athletes - sloped shoulder, short cannon bones, correct legs.
Here is a picture of a horse that was at our barn - he was 4th in the Green Conformations Hunters at Washington and Cap Challenge so he is a good example. http://pets.webshots.com/photo/28398...29367528jcZAUQ
Kenny Wheeler who is a hunter breeding guru loved this horse, so that is a safe bet that this horse is a looker.