Henry Blodget at Internet Outsider has some great figures about how online advertising in the UK has now exceeded newspaper advertising and there is no reason to expect that the same won't happen here too...
According to IAB, online advertising spending in the UK in 2006 exceeded newspaper advertising spending. This amazing fact received less attention in the U.S. than it should have.
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According to Morgan Stanley figures for 2005, U.S. newspapers still generate about $49 billion in advertising revenue (including classifieds). This compares to about $16 billion last year for Internet, $45 billion for broadcast television, and another $19 billion for cable TV.
Unless there is something structurally different about the UK market--please weigh in on this if you know--the UK statistic suggests that 1) the US online advertising market still has massive growth ahead of it, and 2) U.S. newspapers have not yet begun to feel the pain.