1) Read tons of blogs first. I recommend that you read at least 50 blogs for two weeks before you start. Get an RSS Aggregator. That's a must. Learn how to use Feedster, Pubsub, and Technorati.
2) Show your passion for your company and your products. If you aren't passionate about your products or your company (in a good way) then it's probably best that you don't write a blog that'll be identifiable with your company.
3) Help other people share their passion (interview workers who you notice staying late to do something "extra special").
4) Try to answer any concerns bloggers might have. But, be careful. Work with PR teams and marketers in your company so you know what their stance is.
5) Take some risks. But know the consequences." - Robert Scoble.
[Debbie Weil]