Not long after Odigo added functionality to its instant messaging software to enable its users to communicate with AIM users, AOL shut them out. That’s not surprising, given that AOL has done that to everyone who’s tried to tap into the AIM network. The fact that AOL controls a huge percentage of the instant messaging market is a big, big problem, because they have no desire to interoperate with anyone else. Standards are desperately needed in this area, and nobody seems to be working to make those standards fall into place. AOL is clearly trying to protect its market, and while Yahoo and MSN have both made noise about pushing for standards, neither of them have published the documentation for their IM standards. There’s an open source IM effort called Jabber, but I haven’t been tracking their progress.