I've always thought the smartest way to go would be to have 'blocks' of MMOGs, kind of like Sony's Station service. That way they rope you into being a customer, and you can play any of that publisher's MMOGs.
Strangely, Sony is the only one who went in that direction. Does this give them an edge? Time will tell, but I guess since WoW has grabbed the lions share of players it may be a moot point. On the other hand, tough times should put the validity of a business plan to the test.
With NCSoft growing in the MMO market like it is...I would expect them to be launching a "station pass" like service soon. NCSoft has Auto Assault coming, CoH, CoV, Lineage, Lineage II, Tabula Rasa. They also have Guild Wars..but you don't pay for that one in the same way... Still, I think once Auto Assault launches, they may start looking into that.