Just in case you haven not yet encountered or heard (enough about) the financial, economical, media and advertising crisis or, you want to understand a bit more about what (might) happen to you, to US.
Here you have the 147 page MorganStanly presentation from Mary Meeker and others
Link to Docstoc
One example chart:
Analysis of the relation between real GDP and US Ad Spend
(from a regression analysis)
If GDP is in plus, advertising spend is doing better, if GDP is zero or minus, advertising spend is even worse.
via Berry Graubart on Content Matters