Did Microsoft buy an IM monopoly with Skype purchase?

More and more analysts are coming round to the idea that Microsoft’s Skype purchase was strategically a very wise more, but we still hear all to often, largely from tech bloggers, that the $8.5 billion will soon be wasted due to Google Talk taking over.

The truth of the matter is however that there are really only 2 big IM networks in the world, Skype and Windows Live Messenger, and the two combined likely have over 80% of the IM market. Of course no-one knows how how many active Google Talk users are, and Google has never told anyone, but as it is confined to a percentage of the 200 million Gmail users, likely not much bigger than Yahoo Messenger, and when Skype and Messenger merge the network effect will be immense, ultimately locking out other smaller IM networks.

Microsoft has many plans for Skype,  but merely owning 80% of IM may well be worth $8.5 billion all by itself.