But arent the case the same
negative
There is a better edge (relative!) to the older stats as there are better powders for the '06, but the 308 is still more accurate.
You are too confused by speed being the determining factor to accuracy. Just because you push the bullet faster than that same bullet in a slower cartridge does not mean it will be more accurate.
I would not worry too much to the difference unless you are bench shooting or into competition. The 30-06 can be you choice if you want heavier bullets. The lighter ones, the 308 can match, and sometimes EXCEED the 30-06 - remember it is a little higher pressure than the '06, but not much.
You most likely would get a better response in the competition forum than here, although most re loaders know about accuracy too and I am sure all of them know that consistency from shot to shot is what constitutes good accuracy, not the "fastest recipe" around.
It mostly has to do with "which can burn the powder the most uniformly each and every time" and a long column of powder is not good for uniformity. That is why the shorties with way less powder can match a larger case's round with accuracy. Being a bigger case is useless unless there is a perfect powder that can fill it up and not be over pressure. Many times there isn't and a smaller capacity one will be better because there is less empty space or a powder that is more consistent.
a good comparison here:
http://www.snipercountry.com/Articles/AccuracyFacts.asp
although I think the 06 can do a little better now a days with better powders.
As far as which rifle to get - I would focus more on if you want a short action or not, or if you want to shoot heavier bullets or not. Keep in mind that many 06's twist rate isn't all that optimal with heavier bullets (such as 220 grainers). I would rather use a 338 or something if I needed to use such a heavy bullet. I prefer to have things in the "middle" of their capabilities rather than on the extremes. But that is me, and I do have 220 gr solids for 30 cal, so go figure!