Ceritification is one of things that cause a lot of flame. Some people say this is critical to have a proof that your knowledge and it helps to find the job. Others insist that managers learned to be suspicious about certification value because theoretic knowledge it provides is of little help to day-to-day work.
I myself is rather of the second type of managers. I ground my conclusion on the fact that the best testers I worked with were not certified. On another hand, I know average professionals having tens certificates.
Of course, when comparing two idetical candidates (which is a very rare case), I would pick one with a certificate. So, the certificate wins but with a very small (insignificant) lead. This means that you need to think twice before investing into certification.