To clarify what Bryan said about chines (edges, I'm old school)...
The reason you want edges is for better tracking and carving in and out of eddies. In short it gives you better control because the edge grabs the water. This is excellent for big water paddling, which is why boats like the Diesel have very pronounced edges, partially due to the flat bottom. This is a river running boat.
NOTE: To make an edge sharp you either have to flatten out the bottom (sometimes only slightly), or flatten out the side wall (again, maybe only slightly). River runners tend to flatten out the bottom, because a flat and often nearly vertical side wall is more difficult to roll. And, both river runners and creek boats are designed to be easy to roll, requiring rounded side walls.
Creek boats don't have sharp edges for two reasons. A) the edges catch on rocks, resulting in spectacular down stream flips and botched lines. B) if they have a sharper edge, then they probably have a flat hull, which won't roll off the side of rocks as well. The hull sits completly flat against a flat rock, and your abs often aren't strong enough to roll the edge of the boat off of the side of the rock. This is a shallow water type boof (Luke Hopkins did a writeup on this for LP).
Hence, creek boats are made for shallow creeks, and river runners are made for larger volume rivers. That being said, if a 'creek' is flooded and has massive holes, wave trains, and hardly any rocks that you will be scraping over, then a river running kayak such as a deisel or h3 will probably perform better on that 'creek' but it still doesn't make it a creek boat.
ps. M3 kicks the bosses ass. haha