Nobody will be happy, but there's really nothing they could do about it at this point. Ride it out with the handheld, and wait for the next opportunity for a Wii-like hit.
For me personally, the Wii success didn't translate to 3rd party support, so it's hard to get excited about their sales anymore. As long as they keep producing games and don't Dreamcast on me, I'm happy.
As for the PS4, I'd be careful with assuming it's going to do better than the PS3 just because Sony isn't screwing things up as much as last gen. Sony can't afford the same losses it did the last time around, and more importantly, graphical updates are becoming less and less important. It'll take a long time for sales to ramp up (price needing to come down to ~$300), and in that time, there's no telling what'll happen in the market.
For example, with PS4 abandoning all backwards compatability, it makes it a perfect time for anyone on the fence to jump ship. And with the PS4 being nothing more than a glorified PC, what's stopping a competitor like Valve from giving them a run for their money? I've seen virtually no talk of the Steambox on here, but with what we've seen from Sony so far, they look ripe for the picking.
