Definitely yes for the following reasons:

1- increase product and company visibility

2- start a 2-way communication channel with your customers/resellers/employees

3- differenciate yourself and your company from the competition

4- give a web 2.0 look & feel to (part of) your company website

5- assess customer inputs and needs

On the other hand, corporate blogging is not so easy when you start from scratch. You should get some help for your "corporate blogging" project. Companies like french www.blogAngels.net can help you define and successfully execute this kind of project.