This just released report (April 2007) seems to agree with many of the findings of the Dec. 2006 Kaiser findings.

More evidence of teen and pre-teen multi-tasking

Kids between the ages of 2 and 12 years old spend more than a quarter of their leisure time doing
two or more activities at the same time. Favorite pastimes among the sample group included reading,
using the computer, spending time with friends, listening to music and watching TV. Kids today have
plenty of leisure time, with 2-to-11-year-olds averaging roughly 68 hours a week, and 5-to-12-year-olds
averaging 58 hours. Toddling 2-to-4-year-olds are true layabouts, averaging 94 hours of leisure time every week.
(Source: NPD Group's "Kids' Leisure Time II" report, cited in Emarketer news story)