Walter Carl and John Cass have released a study entitled "Blogging Success Story" that details the best practices and traits of successful corporate bloggers. I'd really encourage you to give it a read if you contribute to a corporate blog, or are thinking of starting one.

This excerpt from Walter's blog provides a great summary of the best practices described in the study.

• Culture: If a company has particular cultural traits worth revealing or a bad reputation it wants to repudiate, blogging can be an attractive option.
• Transparency: Critical to establishing credibility and trust with an audience. People want to see an honest portrayal of a company and know that there are not ulterior motives behind the blog. Blog audiences respect a willingness to disclose all points of view on a subject.
• Time: It takes a lot of time to set up, research and write a quality blog. Companies need to identify a person who has the time or whose schedule is freed up to make the time, or need to engage a group of people to share the responsibility.
• Dialogue: A company’s ability and willingness to engage in a dialogue with their customer base about topics that the customer base is interested in is critical to its blogging success.
• Entertaining writing style and personalization: A blogger’s writing style and how much they are willing to reveal about their life, experience and opinions brings human interest to a blog, helps build a personal connection with readers and will keep people reading.