Which Newswire Service Is Best For Journalists?

I’m trying to get some feedback on which newswire service is best for journalists who want to be notified via e-mail the moment a release from a particular company or with a particular word hits the wire. While I already get so many releases sent directly to me, and via RSS feeds and Google Alerts, I’m interested to hear what others may be using. I am looking at PRNewswire.com’s service for journalists, but so far have not been impressed with the releases it is sending me. I welcome any feedback in the comments section or to me directly.