Just a few thoughts on my experiences with the retail release thus far.
UI - fairly similar to the default WoW one. You have your hotbar, mini-map, chat pane, health/mana, and target meters, all that good stuff, but I can't help but feel that its a little bit clunky. Could be because I am used to a fairly tricked/modded out UI in WoW for the past couple years.
Questing - Quest are also fairly similar to WoW where the questgiver send you off to gather some materials used in their trade, to kill off someone, or to generally help the Resistance (I am still in the newbie area having just dinged 14). I do like that the mini-map has big "X's" to mark quest locations, or if in an instanced area, a shaded region generally showing you where you had to go. Made navigating very helpful. The leveling rate is also very fair from what I have seen, both quest rewards and per kill. Not sure what my /played is but 14 seems reasonable for the time I have put in thus far.
One thing I didn't like was that when grouping for one chain, it appeared that your group mates did not appear on the mini-map, so it led to a few "where did you go?" moments, and made finding each otehr again difficult. Also getting the group formed seemed to be a little bit more clunky than required due to the instanced nature of the game. Could be because I just don't know the interface yet but it was a pain in the ass the first go round. Should be better when I form another group but I will report back if its still painful.
I also found it amusing that the are automatic guild announcements when a guild mate levels up. No more having to type "ding" yourself. Kind of a neat notification I thought.
PvP - I have roled on the RP-PvP server (Cimmeria) and only been ganked twice. Both from the same assassin, and mostly because I was in a zone where I should not have been at my level. I just made it too tempting for the guy to 2 shot me hehe. I have not experienced any of the battleground-like games yet so cannot comment on how organized PvP works.
I also read that the PvP is free-for-all, which means that unless guildies are grouped together, guildies could fight/gank each other. Kind of a fun aspect imo since you can't count the times I have wished I could fire a frostbolt into Madson.
Combat - I am not sure their their combat system is as revolutionary as the devs made it seem as I have yet to actually move my shield defenses around in a fight. I just leave them protecting all sides equally. That could be the reason that I have died A LOT in my travels thus far, but I think the bigger reason for that is the combat just being different from WoW. No auto attack so you always have to hit a key to attack (melee or to cast). Plus I think necromancer's are very shitty early in the game. At 12 or so I really noticed improving and actually being able to take on 1-2 even level mobs readily, whereas prior to that I would die on a 1-1 fight regularly.
Graphics - Pretty decent. I am playing on medium settings at the moment and experience very little slow down. On high I did see a little stutter here and there and probably could bump it back up. The art style is definitely more realistic than WoW and appears a little bit darker. I have found my necromancer spell casting animations do be quite blah, so I was a little worried. But then I saw the fire effects from a demonologist, and was impressed. Must just be hit and miss on how some spells look.
Overall I find it a fairly decent game, but it has not blown me away. That is mostly attributable due to the fact that I have not played with anyone I know. Sure I have guildies from the WoW Horde side (non-Avians) but they are either high level or play at a different time from me so no opportunity to meet up and chum around. Makes for a fairly lonely game.
I do like the fact that I do not know the Conan lore and that the storyline, characters, and world are fresh. Just wish I had more friends in game to fool around with.