"That depends. I have never met or talked live to some of my overseas colleagues. We communicate by email or IM. With some folks, it's all business, and that's ok. Their personality and capabilities still emerge over time, but you do have to be extra courteous and careful in these exchanges to avoid misunderstandings. Written communication is often best in these situations, because either you or the person on the other end may be functioning in a second language, and writing allows you more time to be more precise.
For local employees, it still depends. If it's a private or very complex matter, or an open-ended one that involves alternate generation of ideas and mulling them over, then I am going to walk over to their desk. My next go-to communication method would be IM. You usually get an immediate response, and while you can get into side conversations, no one is offended if you stick to the matter at hand. If you just have a quick question, IM is a great tool. These days, I'm probably not going to use the phone unless I know that the other person prefers to communicate that way. Some people don't type very well, or don't feel that they come off well in written communication. They'd rather talk on the phone. On the one hand, that usually ends up taking longer, but on the other hand, it allows you to nourish your bond with a colleague. I would use email more for formal communications where I want some documentation of the conversation, or when something is too complex for IM, is not time-sensitive, and there is no reason not to give a person the time he needs to consider his answer. I think a person should be sensitive to the benefits of face-to-face conversation. You have to balance that against the instant gratification you get from IM exchanges."
