About the game: This is the 3rd expansion for World of Warcraft (the other 2 being The Burning Crusade and Wrath of the Lich King) and it is the one that changes the old world from the original game (for the better).
Controls: These have not changed since the first game and if you have ever played a massive multiplayer game its pretty standard fare.
Graphics: This aspect of the game has changed quite a bit since the last expansion and for the better. For a game that had pretty mediocre graphics when it first came out, this game looks quite awesome when at higher settings. The shadows, colors, textures all are superb.
Sound: Blizzard has always been pretty good about sound and this expansion is no exception, they redid the music for quite a bit of the old world and added a ton of new music to the new zones. The music is always very good at setting the mood and very epic at times as well.
Gameplay: Blizzard has decided to revamp the old world and at the same time make the early leveling experience a much smoother and better experience. Almost every zone has changed and even if the zone has not changed graphically, it has changed leveling wise. You will no longer be jumping from a zone in the south to a zone in the north. Each zone leads to the next without any issue. Almost every zone has a story that really takes the leveling experience to a new level (Go to Westfall and Redridge for examples of this).
There are 2 new races and like the new class that was added last expansion the starting zones have been done with a fine tuned comb. The new races are Goblin for horde and Worgen for Alliance. They are some of the best examples of unique experiences and new types of quests to be found in this game.
The only issue really is that once you leave the old world and enter Outlands leveling is not as smooth or quick. Of course, this just leaves the game open to a new expansion.
If your are level 80 then you also have a very linear experience, though you will using your home city as a hub to get to each of the new zones. The new zones are just like the old zones in that they are done very well and have a story that makes the experience awesome.
The 5 man dungeons are very well done and blizzard made every dungeon now have quests inside to make finding the quest giver easy. The heroic versions of the new 5 mans are no joke and some of them will be very difficult to PUG. I would not recommend it unless you want to wipe for hours on end.
The new raid instances so far have proven easy (though coming from a guild that has killed HLK anything would be easy) but we have only gotten about 6 bosses on normal so far. Some of them have unique mechanics, but nothing that I have found super awesome.
In the end the game is the same standard lvl, instance, loot, but its still very addicting and very fun. I did not mention the pvp portion of the game, because I have not experienced it first hand, but I hear that it is quite good as well.
If your new to wow, the game will be that much better. If you are an old timer you'll find some very welcome changes.