The verdict on 2006 is final, at least according to Nielsen Monitor-Plus, and it looks like the Internet and spot television in Top 100 markets were the major drivers.
The report was that advertising spending on the Internet increased 35 percent, while Internet ads in the Top 100 spot TV markets rose 9.1 percent, followed by Spanish-language television and outdoor programming, both at 8.1 percent.
According to the official press release, "Growth in a number of media remained flat or slightly down" with a list including business-to-business magazines, coupons, smaller spot TV markets, network radio, and local newspapers.
According to the study, dramas overtook situation comedies for the most appearances of "brand integrations," largely due to the growing number of dramas as compared to sitcoms on the air. According to the press release, "American Idol featured 4,086 product placements, with more occurrences than any other program, a 17% increase over 2005."
However, as Katy Bachman points out in MediaWeek/AdWeek, "Product placements in prime-time network programming also leveled off in 2006 with a decrease in the overall number of placements to 79,701 from 102,793 in 2005," she writes, attributing the switch to more dramatic programming also leading to this change, since dramatic programming tends not to include as much product placement.
I would argue that this is largely because the industry has not developed a consistent way of dealing with monetizing organic product placement in narrative worlds, a change that would be to the benefit of all involved and would lead to greater avenues of income for dramatic programs.