The question could be generalized to include the PSP and XBox 360 by asking "How much has the transition from a graphics dominated industry to a gameplay dominated industry cost developers and stores?" which is not an easy question to answer.
The reality is that most retailers supported all systems so their unexpected losses from the PS3, PSP and XBox 360 have been balanced against unexpected gains from the Wii and Nintendo DS. Developers (on the other hand) tended to favour the PS3, PSP and XBox 360 over the Wii and Nintendo DS which has resulted in a shift of money towards the developers who gave reasonable support on the Wii and DS; being that Nintendo was the primary supporter of their systems they have benefitted the most but some developers who provided decent support have also gained from their backing of the Wii/DS.
