To each his own.
Personally, I find WoW to be a great way to relax after a stressful work day. I just mindless hack and slash away at solo PVE. If I'm feeling a bit gregarious, I have the option to group for instances, quests or raids. Or I can chat with other players.
I can relate to what T-2000's saying. Sometimes I get caught up in the game. Then I find myself getting to work really late all the time. That's when I just find something else to do for a few months. If I'm still into the game, ok. If not, I'd ebay my accounts. Mind you, I should stop playing on the U.S. Pacific servers.
Ideally, play it, but don't live it.
However, I miss playing Ultima Online. Just because it was so profitable. When I quit the game, I ebay'd 3 castles at USD 700+ each, and 7 keeps at USD 500+ each. Not to mention all the 2-storeys I sold at USD 100+ each. I don't miss the PK'ers and other grief players though.
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L70 Prot Warrior Kara Off-tank
L70 Holy Priest
L70 Shaman
L70 Druid
L70 Rogue
L69 Druid
L69 Rogue