Although known for a long time, I hereby declare that bandits are in Skyrim, obviously!
Come to think of, I've never seen an RPG without bandits! There were bandits in FFVII right?That aside, so far we've only seen the ones called "Bandit" - No marauders, hedge wizards or highwaymen, not that I am doubting their presence in Skyrim at all, so fell free to consider them a part of our adventure.
Like in Oblivion, bandits will, unless scripted, draw their weapon and attack you on sight, not leaving you with a chance to surrender you possessions and leave in blissful peace. As always they will probably be a welcome morning exercise for swinging our blade and wielding our flamethrower firespell. Basically they are just cocky canonfodder.