The online ad market gets more interesting by the week. Yesterday WPP Group, a huge advertising conglomerate, agreed to acquire 24/7 Real Media.

Microsoft, not to be denied an ad network, purchased Seattle-based aQuantive — for an amazing US$6B in cash, an 85% premium. That means Microsoft gets Avenue A | Razorfish and Atlas.

This of course comes on top of the Google-DoubleClick and Yahoo!-RightMedia deals. Now ValueClick‘s shares are up. Will they be picked up by Ask.com … or perhaps Omnicom Group? Or are we done for now?