LeftField I think it's fantastic your son plays so imaginatively. If only all kids could. Some kids can't with or without computers, I agree. My 2yrold ds learn't far quicker than my 4yr old ds. They're all differnt!
My evidence is anetdotal, through my own visual and written observations of children I have worked with. I'm a science grad. and primary teacher (state trained and a Waldorf teacher), I'm also studying (finishing an Educ degree and looking at post grad research in Educ) and I'm currently working part time in my chilren's Playcentre doing a lot of written observations of children for our session and individual planning. It's pretty interesting, as you can imagine. I've noticed the effects of TV more on the preschoolers I work with at present (although many of the non-steiner familys in our state pre-school don't let their kids use computers, but most watch TV though), and when I was teaching primary full-time (pre motherhood) it was pretty obvious by the chilren's play who regulary played/worked on the computer, it was usually quite a focus for them. In my eyes computers (and TVs!) aren't nearly as good a role model for children as their parents/friends/family/teachers were. There's so many ways to sepend your time. We all see things differently though. When you take, or are given, the time to closely and carefully observe a range of different chilren it is suprizing what you see. And it's an honour to be allowed to do this.
I don't hide books from my boys. My 2 and 4 year old love thier books. We read and sing to them little stories and many nursary rhymes, they 'read' to each other and love their books. I also tell and sing to them alot without books. They love that too. I had several children in my Steiner class one class years ago who had taught themselves to read. I think thats wonderful. They wanted to, no one pushed them too. They were both girls. In general I do see some pretty big differences between most (not all) girls and boys when it comes to learning to read. Many boys do better to learn slower, and doning physical things. But each individual is differnt of course.
Oh, I learn't to read at 6-7yrs at a Steiner school and that hasn't heald me back. I've been a bookworm since then and so have all my sibilings (they aren't all girls..).