I use my Browning .280 BAR with Winchester 140 grain Silvertips for Western Oregon Deer, although I've used it to hunt Mulies and Bull Elk in Eastern Oregon as well. Flat shooting, good all around gun.
I have to agree with Goosehunter. Somewhere between the 25-06 and 270 would be ideal. The only exception would be if you are hunting an area where it is likely you'll have a tag or chance to harvest bigger game animals. I've always liked the 308 b/c it will have a little more knock down power to take out a bear if I see one during bear season. A lot of bears around here are killed by chance and being in the woods at the right time. It's good to have the extra power if needed. The 308 is also an excellent long range caliber.
I would have to agree with that. The .308 is an awesome caliber and one that at some point I will probably end up owning. It will probably be in a unique rifle though like a sjingle shot (ruger no. 1 maybe). The point about encountering larger game is a good one as well. A big component to be added there is that bullet choice is going to need to be looked at to. If there is a chance that you will get a shot at a larger animal with a more hardy skeletal system, you aren't going to want to use that same fast opening, rapid-expansion bullet that you would normally use on deer. You'd have to find something to fullfill both roles. Which in this day in age of a million bullet choices... shouldn't be all that hard.
I also think it depends on where and what type of deer. out here if your hunting blacktails a 223 or 243 is about right as they are a small deer, for whitetails or mulies a 243 or larger would be good, i use my 30-06 for everything and to me its a little much in th way of blood shot meat. I would love to add a 270 to my collection and that would be my dedicated deer gun.
I've spent countless hours either on my hands and knees or bent over, messing up my back, looking for blood. One such instance I remember most was a hog hunt a few years ago in Mississippi. I had never shot a hog so when I poked a hole in this guy; I was determined to find him. Wearing snake leggings, I crawled on my hands and knees through the briars and the brambles and bushes where a rabbit wouldn't go. I found a spot of blood here and there but never the pig. And lucky for me, I didn't find...