To OP: Have you installed any mods? Have you disabled the Enemy and Location Markers in Compass?
I became bored of the unmodded game in about 100 hours too. The reason was mostly all the markers in the Compass which made me not use my brain. After I disabled the Compass (and later just the markers) the game became much more interesting.
Edit: http://www.gamesas.com/topic/1359766-did-you-like-the-unmodded-game-mainly-for-pc-players/
This + what shyguy said in post 20. I am on PS3 so I cannot mod, but at least I can turn off the HUD. Combine that with roleplaying/no fast travel and the game can be very interesting. I'd probably be a little bored too if I had not turned off the HUD because I was always staring at the compass icons, the red enemy dots and the sneak crosshair. When those things are front and center of your screen how can you not stare at them? Once I turned off the HUD, it let me really get into my characters because now I was looking at NPCS and listening to them to figure out whether they could see me or not.
I was really disappointed that Skyrim does not contain enough clues in the gameworld (lack of directions) to let you complete quests, but once I figured out how well they did with putting clues in the gameworld to let you know if you were hidden or not, I forgave Bethesda for the lack of directions.
I preferred a class system with real racial and class distinctions with attributes and more spells and spellmaking etc. etc., so I could see why a TES player could get bored or disillusioned with Skyrim, but I have found enough of interest here to make me excited to keep playing. I have seven different characters each with their own unique personality and build.