After 30 years as a journalist, I'm switching careers. I left BusinessWeek when it was acquired by Bloomberg on December 1.  Today I will begin working for IBM as a communications strategist and content creator. I look forward to helping out with communications and marketing for one of the best and most important companies in the world at a time of tremendous change in media and advertising. There's a great opportunity now for companies to communicate directly with their constituents in new ways--to reinvent communications. I want to help lead that transformation. I say goodbye to journalism reluctantly, but, the way I see it, journalism left me rather than the other way around. There isn't much of a business model these days for the kind of serious, in-depth journalism that I practiced. Meanwhile, the communications revolution beckons.