If they want the PS3 to last that long, it will be easy: MAKE MORE GAMES! Not shovelware, mind you, but good-quality exclusives, stuff that sets the PS3 apart from the competition. Yes, the PS3 is technologically superior to the 360, whether the XBox fanboys care to admit it or not, we get that. But you know what? NOBODY CARES ANYMORE!! Chrissake, you think flaunting that fact is enough to make everyone trade-in their 360 for a PS3? People don't buy consoles for the console. THEY BUY IT FOR THE GAMES!!
Once the Arc or whatever it's called is out, ditch all other stupid peripheral projects for, like, a year, and start work on some brand new franchises, showing us (and, more importantly, third-party devs) how all that power can be used. Make them fun. Make them interesting. Make people say "Wow, you know what we should get? A PS3, because it has [cool RPG X], and [awesome platformer Y], and [weird-yet-extremely-cool-looking-game-that-noones-ever-heard-of-before] that's coming out in June!" Because that's what people look for when buying consoles. At least, that's what I look for.
The PS3 has recieved a bunch of great new titles recently, like Uncharted 2 and Heavy Rain. But they need more games, and more new exclusive franchises if they intend it to survive for a decade, and possibly longer.