Walmart has recently committed itself to aggressive pricing on LED bulbs; 800 lumens would be typical. I've seen LED flashlights that would throw a beam a mighty long way and practically blind you in the process, so I'm guessing that the real limiting factor here as far as cost and brightness go isn't the LEDs themselves, it's the electronics that you need to step-down and regulate the AC line voltage.
»[Green ] Walmart gets aggressive on LED bulb pricing
LEDs might very well be a cheap and near-perfect match for DC systems like solar. In fact, I wouldn't be at all surprised to soon see new homes have their lighting systems wired up directly for DC, with AC used for everything else. Or at least to have some shared AC-to-DC conversion systems, maybe at the fixture level. This would no doubt eliminate at lot of the cost of the electronics for each bulb.