Here is what I think...it depends. Having a formal process tends to force managers into providing feedback on a somewhat regular basis. However, how relevant is the feedback if it is provided 6 months after the fact? Not to mention the administrative burden that comes along with trying to manage this process. Most managers are not excited to stay on top of the review process and need rather a lot of nagging to get it done. Some employees love the process, some dread it, some think it is a waste of time. However, it DOES provide a structured way of providing feedback, and creating documentation for all sorts of go forward action - compensation, advancement, terminations.
Can managers provide timely and relevant feedback outside of a formal review process? Of course they can. Can employees ask for timely and relevant feedback when it is important for them? Of course they can. But this will represent a major shift in traditional thinking for the average organization. For some reason, and I do count myself in this group, I get quite a lot of bizarre comfort in having a paper trail, even if that trail had to be beaten out of the manager, and may not be relevant anymore.
I once heard the best performance review form was a blank piece of paper. And I agree, I love the concept that a manager can sit down with an employee on a regular basis and just talk. Of course, loving my paper as much as I do (I am still a bit old school that way) I would hope that the manager writes something on that paper. Then I would like the employee to write something on that paper. And it needs to be done on regular basis.
Personally, with my clients, I am moving them towards a less formal review process. I still recommend a process of sorts, but I have moved away from the traditional approach. Not all the way, I am not quite GE forward thinking...but I do suspect a number of organizations are getting there when it comes to the review process.
Here is the link again to participate in the poll.