Everquest 2: The Shadow Odyssey is a much welcomed change of pace as an expansion to EQ2, which I strongly recommend.

User Rating: 9.5 | EverQuest II: The Shadow Odyssey PC
EQ2: The Shadow Odyssey brings a new element of game play into the already bad ass world of Norrath, the expansion focuses largely on group instance dungeons that you can do daily quests in to receive Void Shards, which is a new form of currency for purchasing the new, uber, gear. EQ2: TSO also brings a lot more solo content to the table for the level 70 to 80 character. The new continent (or zone) added with this expansion is called The Moors of Ykesha, and it is by far the largest single zone in the game as of now, but unlike you may first assume, traversing it is relatively painless and enjoyable; and of course it is ridden with solo quest lines that actually provide you with some nice rewards.
So over all I would say that picking up The Shadow Odyssey expansion is an absolute must for any Everquest 2 player, and for anyone who isn't an EQ2 subscriber already, I strongly recommend looking into one of the week or month long free trials. Everquest 2 is definitely a game that has changed my perception of what all one game may offer to a person.