I still like to get both red and blue first, if possible. It depends almost entirely on the champion, and also where you want to end up after first clear. Some can gank after an entire jungle clear, some need to back after half their jungle and get their Smitem(tm). For example, with yi, I start red, go wolves, get gromp, go blue. I'll either gank top then, or go back and get skirmisher's/stalker's. With Rammus, I'll start blue, get wolves, get red, get krugs, then back.
You can start krugs or gromp for the smite buffs, but I find that they don't really help that much. They don't increase your clear speed dramatically, and they don't deal as much damage as blue or red camp, the first of which you do you will no longer have smite for.
I almost always recommend smiting red buff though; the health gain back is so useful.