BusinessWeek covers the recent departures at Microsoft. What's interesting is that they point to the role of blogs and email in laying the culture bare. While there is no question of the impact of both these mediums, the thing that had a real impact for me was the testimony of computer scientist Kai-Fu Lee which was heavily reported in mainstream media. Dragging ex-employees through court only to have this kind of testimony revealed just ain't a good thing.
Tracking your employees' reporting - and the tone of those posts - should be a priority for any communicator. Not to effect change on any one individual(or seek retribution, god forbid) but rather to create a new barometer of employee sat, especially given that small clusters of vocal employees typically influence the masses. In the Participatory Era you had better be tracking every dimension of participating. Tracking the dialog will give you a feel for whether employees really want to participate in your company.