Microsoft is no stranger to throwing huge amounts of money at markets it wants to break into – it did it with the Xbox and it’s in the process of doing it with its new Surface tablet. But even in this context, the $1.2bn it has agreed to pay for enterprise social network (ESN) Yammer seems steep, especially for a company that probably isn’t making any money (Yammer is notoriously guarded about its financial figures).
The deal shows the tech world’s belief that business-oriented social networks have a real future. The market, though, is more crowded than you might realise, with a plethora of services on offer. So which one is right for you?



