Christ guys.
It's not that hard. Casual versus hardcoe gaming isn't about difficulty, it's about the way you play and the complexity that you are mentally capable and/or willing to accept from the premise of a game. I'm certain there's levels of Angry Birds or Peggle that are plenty difficult, and any hardcoe noscoper with every achievement in every majour FPS in the last ten years, or an hardcoe RP'er that beat all the main lines in Daggerfall the legitimate way without cheats or exploits on high difficulty and maxed out their character, or a chess grandmaster would have trouble just coming into because damn, simple things can be difficult without requiring dedication.
Likewise, games that have in the past been made to appeal to hardcoe gamers can sometimes be easily mastered by casuals, see Morrowind. All those skills, attributes, numbers everywhere, your weapons could miss... But as somebody said earlier, it wasn't
hard, you
learned from it. It was, however, complex; It didn't cater to casuals, it was just fairly accessible. It's a
midcore game, and that is generally accepted by most "gamers" to be where a game should lie, not in the incredibly cryptic and tedious ways of, say, the Witcher series, or in the infantile and condescending lack of gameplay and overplayed humour of the Fable series. (Don't bloody get me started on pretty much any Bioware game ever. I don't even know where that falls, but it's bad.)
Casual games are games that
-Don't require much time to learn or master
-Don't have many variables on or depth in gameplay; They essentially play one way or a few ways, and you're only affected by what kind of bird you have in your slingshot or how much health, magic and stamina your character has (blatantly making my point cough cough)
-If they're in a series, cut out features and flanderise in-jokes as they progress
-Provide some form of hand-holding throughout the game, so if they don't want to (or even if they do), no player has to exert their minds; This manifests in hints systems, onscreen "walk here. Point here. Hold the shoot button for x seconds," and explicit directions to any goal through other means
-Have a "safe" world in which, unless you just really [censored] up and run out of ammo in an arcade style game or you die or something, you cannot make the game "over" or lose or even close paths to yourself,
even if you try. Death is usually penalised by returning to the last save in games where applicable.
-Rather than rewarding the player by
changing the dynamic of gameplay and increasing the level of opponents you can face or difficulty of levels you can complete, they reward the player with frequent (albeit admittedly highly rewarding the first several times) "flavour screens" wherein you get things like fireworks, cinematic kills, "badass" cutscenes and so forth; For an even more blatant example of this faux pas (in a "serious" game it is a faux pas, though it fits the mood of some games), look to the currently popular Lollipop Chainsaw, which has giant starbursts combined with its cinematic killcams that pretty much screams "BONUS YOU'RE GREAT WOW HOW DID YOU GET SO GOOD YOU TOTALLY BEAT THE FIRST HALF OF LEVEL ONE WE'RE PROUD OF YOU SPORT" across the screen.
-Reward the player for repeating parts rather than for increasing in actual skill; die to a boss? Go grind then come back. Hit the ceiling in Tetris? Get better at Tetris you git.
You can see that Skyrim doesn't meet (or fully meet) all of these points, but it certainly meets enough that if there weren't a few points of difficulty, if the perk system didn't add a little depth to your character and if the world wasn't so immense, I'd actually write it off as the first game in the series to be a
casual game. A sixty dollar casual game of the year, how about that?
On another note, not suggesting it'll ever get THAT bad, but Skyrim is about as "casual" as the first Fable game, in all regards except the lack of railroading (the world was not fully explorable in Fable). We're kind of on a slippery slope as far as quality goes, and the blatant draws included to the Fable and similar communities
Spoiler such as a "bunnies slaughtered" stat on the character screen, the clairvoyance spell if following a path on the ground in the direction of a compass point is too hard for you and big cinematic spells with nearly identical animations to similar spells in Fable that are also laughably ineffective for the same reasons (while they look cool and do a lot of damage, they have very low DPS because of charge time and can also be interrupted, so it's a big assumption that you'll ever even get to use them in combat)
don't do much to encourage faith.