Khan Academy is awesome--a fantastic resource. As for Starfall, though, I never saw a need for it. It was fun, but nothing I couldn't provide myself.
I certainly feel that computers and the Internet are amazing resources. However, I think a child who had no access till 5-7 wouldn't miss much, and I also think a child who was unlimited access CAN overdo it quite seriously. I was at a relative's house recently where the kids are on YouTube and various junk sites almost constantly and I was struck by how little actual playing these kids were doing.
We enjoy an occasional YouTube video and DD sometimes plays on Webkinz (eh) or educational sites, but I still feel my kids' lives are very rich without much of it, at this age. Later, they will need it and use it. Although--this year DD has started using Google in earnest for school research projects, and I am generally unimpressed with what is available for kids her age in terms of good, nonjunky, curated, factual content.
