NomadMan - 4:45 pm on Apr 22, 2012 (gmt 0)
Plus+1 the advertiser migration to search after Panda struck the display network hard.
Consequently CPC on the search network has gone up to get ranked high up the list. Maybe this trend might motivate advertisers to return to the now (much) cheaper display network.
And yes i think it's IBA's that's holding revenue down too. Great strategy to pacify the big click hunters with content based sites made for that purpose only.