Check out Bill's presentation, All about business blogs for a great overview of the subject. And if you like it, check out Beyond the printed page, another presentation from earlier this year.
Note: Bill has quite a few links within the presentations that are worth checking out.
If that isn't enough for you check out Fast Company's recommendations, from Business Blogging for Beginners:
1. Make Introductions.
2. Be authentic.
3. Dress business casual [Be informal but professional].
4. Don't scrimp [on your time commitment].
5. Have a contingency plan [for times when your company hits a crisis].
You might also want to check out The Guide to Corporate Blogging.
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