Games. The PS3 has none. Gundam Mousou showed that good games can sell well. Unfortunately, there are only 2-3 games that have come out that were any sort of major titles (Gundam Mousou, RR7, AC4, and VF5). Software sales are in horrible standing right now for what was such a beast. Sony needs to formulate a plan to get some major support. However, with the fact that most J-devs are going to PS3/360 formats (Last Remant, Trusty Bell, DMC4, ect, ect,ect) the PS3 will always get a 2:1 advantage to the 360 for those games (which is great for the 360, as it had none of this kind of support last gen). This will help it get some decent sales. When the PS3 has about 2 rather large games (+100k unit sales) per month, we should see weekly sales solidify into around 40k a week once a small price drop occurs.
Back from the dead, I'm afraid.
