There are tons of people out there who spend lots of time playing World of Warcraft. WoW is the most popular MMORPG title on the market despite having been around for a long time now.
The iPad is a very nice mobile gaming platform, but the lack of Flash support makes the device miss some of the more popular titles out there like Farmville and others. The online gaming service Gaikai has been used to stream WoW to the iPad.
The game service typically uses Flash to let players play games in a browser window. Exactly how the service is operating on the iPad is unknown. I bet we hear more about it soon enough.