After the big titles hit that the OP mentioned, the games will keep coming. Now that the format war is over and developers are figuring out the architecture, Sony has only one way to go: up.
Eventually the price will go down, drawing more consumers, both casual and hardcore. Improved SDKs will encourage developers to tackle the complex architecture and Sony has been known to be helpful towards developers. Sony has introduced franchises that can continue to grow, be it DLC (R&C: Pirate's Booty) or full on games like Uncharted 2 (rumored but that doesn't take a rocket scientist). The online functionality is improving as well as media capabilities and Home has promise for both community as well as user-generated content.
I'm not coming from a fanboyish perspective, just a rational one. Sony fucked up big time with the first year of the console and paid for it, but now that some of the biggest hurdles are out of the way, they can focus on making it easier for companies to make games and for us to get them.