I watched Extreme Parenting with Jo Frost last week. They conducted an experiment( with young children) whereby half the parents read to their children, and the other half read the books themselves, and listened to a cd with the story. The story contained a couple of made-up words (I think they were objects of some sort) which the children were then asked about. 80% of the read- to children identified the object, and less than 20% of the independent group did. Possibly the parents emphasised the made-up words.
However, it made me realise that children were more likely to take in as story/vocal with parental intervention then when left alone. I guess they engage in the books more.
Not sure if this helps, but I thought it was interesting research.
This is great advice, and I think I have seen this mentioned before. I must agree, when I have read to DD she listens intently and seems to absorb much more. DD is reading daily alone and to us but I rarely read to her, something that I shall definitely do more of.