I intend to keep my slim PS3 (and its games and warranty) until I start to see Gaikai get fleshed out more. At which point, if I decide it's no longer necessary, I'll still probably keep it. Seriously, I never knew how much I appreciated my PS2 until my fat PS3 broke down on me.
I remember when I called Sony about having my YLOD fat model repaired and they offered me a slim for 150$. Glad I turned it down and had it repaired.