Ph.Ds in IT - Good or Bad for a Career?

LordNimon asks: "I'm thinking about getting my Ph.D. (I currently have a Master's) in computer engineering. I've heard all sorts of stories about Ph.Ds being less likely to find a job than their less-educated counterparts, but not a lot of credible evidence. So, I was hoping to hear from Slashdot readers on their experience. Do you think getting a Ph.D. in CompSci or CompEng will improve or worsen my career outlook in the industry? Has anyone witnessed someone being turned down for a job because he had too much education? If you're a hiring manager, what is your opinion on someone who has a Ph.D. and is otherwise already qualified for the position?"