I'm level 24 and Skeletons are still as even a match for me as they were at level 1. With a full suit of Daedric and Goldbrand in my hand a fight between myself and a Dremora Lord is an even fight. If I have any equipment that's not as good as that though then it'll be a tough fight. Unless I have a bunch of potions. Give him a few buddies though and I'm basically toast. I'm level 24 (about to hit 25), I'm not completely powerful yet, but I'm defiantly getting there (my lowest major is 50, but highest is 89). I'd expect 10 levels from now that I'd be strolling about one hitting just about everything that's from the same plane of reality as me like back in the Morrowind days, but then again this is Oblivion. So 10 levels from now the game will probably just amp the difficulty from fair to "Me and my buddies are going to pin you in a corner and stagger you over and over so that you can't do anything" (which as you can imagine has already happened a few times. Mehrunes Razor was a ***).
Basically, playing Oblivion again, I've come to fully realize again just how stupid level scaling is. It's dawned on me that unless I pull that slider all the way to the left I'm never going to be better then anyone or anything larger than a rat. So much for feeling like those 20+ levels are actually worth something more than gear that looks shiny.
God I hope Skyrim doesn't have level scaling like this. New Vegas, with all it's bugs and funky looking textures, defiantly handles level scaling 100x better than Oblivion ever did. Todd Howard better have been paying attention.