I can see the reasons for either party buying Doubleclick – Microsoft is losing the battle to Google in the advertising space and it will complement their offering. Google is already in this space so not sure if there is a benefit for them other than stopping Microsoft?
It would certainly be great for Hellman & Friedman who bought Doubleclick for $1.1bn only 2 years ago.
But there have been several acquisitions by Doubleclick recently (Falk, Tangozebra, Klipmart) so there are multiple ad tracking systems inside the company – I guess there must be some form of consolidation going on internally? Seems to me to be a difficult time to be buying Doubleclick at an expensive price when you look at their turnover. Maybe Atlas is a cheaper alternative? Though even they have just bought Accipiter.