Web Radio...vs Online Radio

Report out yesterday suggests that CBS radio's web traffic is up- which made me think of their acquisition of last.fm.  Which ones are doing better?

Wonder if they are doing anything with these properties purportedly recienving so much traffic?
via mediapost:

CBS Radio's network of radio station Web sites saw its total number of unique visitors increase 30% in December 2008, compared to the same month in 2007, according to Web analytics service OneStat.com, reaching an all-time high for CBS Radio. The online measurement company also noted that unique visitors grew 7% between November and December 2008.

Among the biggest growth stations were KRLD-Dallas, which jumped 133% between December 2007 and 2008; KNX-Los Angeles, up 113%; and WBBM-Chicago, up 104%. Major increases were also seen at WCBS-FM-New York and WPGC-Washington.

To put this in context, I pulled up a compete chart for last.fm, pandora.com, blip.fm (which some of my twitter peeps seem tp be using although I have not really played with it) imeem.com and favtape.com (which I think any of my twitter followers would agree is a favorite of mine).  Since the figures in the article are percentages only, it is not clear if they refer to site visitors or listening traffic. 

Nielsen Netratings puts the CBS radio network at 5.6mm visitors in December 2008, topping a period of significant growth: