The Wii library.
It isn't even close. For a system in its fourth year with the kind of sales it has, you'd expect it to be bursting at the seams with great games, much like the PS2 was at this point in its life cycle. Instead, it was as anemic as it was in 2009. It featured a sequel to one of the best games of this generation but how could a system with 60+ million units sold have such a pathetic lineup just four years in? The fact that developers would rather face bankruptcy and buyouts than develop for the Wii is very telling. The fact that you know Nintendo is going to abandon the Wii full stop once the 3DS comes out, much like Nintendo did with the GameCube when the DS came out.
Runner Up: Final Fantasy XIII - I'm convinced Square dinked around with the game until 2009 when they realized they have to get off their asses and put something out before the money well runs dry. Everything in the game was done better by its predecessors. Annoying anime tropes and insipid personalities that we're supposed to relate to. A museum style game that artificially lengthened gameplay by having enemies with high HP. A game world that we're supposed to give a shit about but won't let you actually explore it.
On Deck: Gran Turismo 5 - Over $80 million spent for a game that took 5-6 years to develop that needed at least another year before release. Like FFXIII, I'm convinced Polyphony Digital was fucking around for most of its life cycle and only got serious about the game within the past year. With this and GT PSP, I don't know how anyone could say they are a premier developer. A high price tag but the quality doesn't match. The massive updates and the all but apologetic statements from Sony since its release are a sign of how they realized they fucked up. Fantards posting photo mode screen shots don't seem to be actually convincing anyone.