At issue are delays to the Riders of Rohan pre-purchase compensation package. Roger correctly notes that Turbine accepted payment in full in advance for pre-purchase of a product with a promised date that Turbine failed to meet. This might in most other circumstances be considered breach of contract. Instead of complaining, I and various others actually praised the move as a way to deliver a more polished product at what may also be a more strategic time.
The guys at Penny Arcade once quipped that Blizzard had developed a business model in which they rent players' friends to them on a monthly basis. No matter how early or late, how buggy or how polished, everyone needs to buy the new content when it is released if they are to play together. (This part isn't unique to MMO's - I've seen friends pester each other to buy new maps for FPS's, and I don't believe any of them ever received a cut from the games' publishers for this peer pressure marketing campaign.) A player who does, as Roger suggests, feel that they are not getting acceptable service finds their friends held hostage - there may be various alternative games on the market, but the odds of reassembling the same group are low.
By contrast, I have the luxury of acting like a pure consumer because there's no one waiting on me to get the new content to fill out their raid group. I never considered pre-purchasing Rohan, because I know from past experience that Turbine will offer steep discounts within a month or two (the new date is not that far from Black Friday). I'm not thrilled with Turbine's decision to bundle in a bunch of extras I don't want to justify a higher price tag for the expansion package, but I don't need to pay the premium that will be required of the captive portion of the audience.
Ironically, the cost of expanding the MMO demographic beyond the traditional social, group-oriented player may have been that the market actually is less tolerant of the things that studios got away with in 2005 when it was a smaller but more loyal playerbase. For good or for ill, perhaps millions of players are now free to quit games like WoW and SWTOR precisely because less of the MMO audience are captives.