Regina Miller provides a nice and simply framework for understanding how your blogging fits into your corporate culture.
Basically if you look at your corporate culture’s norms and taboos as a 4-sided box (with you in the middle of it) imagine one side made of glass; one side made of steel; one side as a locked door for which a key is required; and one side made of the stretchy membrane.
Corporate culture is defined as “the way we do things around here” and you need to beware of the culture of the organisation and the impact that will have on your blogging. As a great example in practice have a look at the Yahoo policy and then compare it to IBM, Plaxo, Thomas Nelson Publishing, or Sun. Each policy and the approach taken to develop the policy provides insight into the corporate culture.