The platforms that currently have clearly defined userbases and are a safest beat to reach profitability (In Japan) are PSP/PS3 for Big/Medium/Small developers, they have the lowest percentage of risk, clearly defined trends and if the aim is to cater the japanese audience they seem to provide the best environment.
Even if this is true, why would it make sense for the developers to start making games for PSP/PS3 now? It would take at least a year to make a decent game. By then, the market for PSP would be almost gone and the market for PS3 would be in decline already. Wouldn't it make more sense for developer to make games on a platform that's healthy and on the rise by the time the game is released?