Three of the old fogies of the tech industry can't seem to get enough of tousling in bed together. Late yesterday, AOL, Yahoo, and Microsoft announced ad partnership that "allows each of the companies to sell each other's unsold premium advertising inventory  -- known as display ads -- by early next year," Reuters reports. So what this tech ménage à trois means is that these three companies are partnering to share more of their banner ads, which the AP characterizes as "some of the less-prized ad space" the companies sell. The announcement of a three-way deal comes off the heels of several unfulfilled whisperings of more monogamous partnerships between the companies, which include talk of a AOL-Yahoo merger and a rumored bid of Microsoft buying Yahoo. One Yahoo executive calls the deal a "'fundamental rethinking' of the Internet ad market"--a market that Google and Facebook are poised to dominate in the near future--but the AP seems to disagrees:

That statement also could be interpreted as a bit of wishful thinking. Microsoft, Yahoo and AOL all need to change the direction of an online ad market that has been increasingly tilting in the direction of Google and Facebook.