I heard an especially annoying podcast by Nancy Flynn on using IM at work. The whole tone of the talk was how companies needed to get control of IM clients because their “rogue” employees might expose them to some sort of litigation risk. These employees are dangerous because they download these IM clients and use them to communicate more effectively.
The solution of course was to lock down everything and establish strict policies. What goes unspoken is that by locking down a tool like IM you drain it of effectiveness. The underlying assumption is not to trust your employees which is where a lot of bureaucracy comes from. The reality is bad employees will abuse any privilege, so you’re just taking things away from your best employees.
Of course personally I try to be careful using IM much because it can be a pretty annoying interruption if you pay to much attention to it.