Online Ad Spending on Podcasts

Are podcasts still to say? Though they have not taken the world by storm as it was predicted to be, they are still growing and that is very important. Here are the online ad spending from 2007 and projected for the coming years:

2007 : $22 million
2008 : $25 million
2009 : $28 million
2010 : $32 million
2011 : $43 million