It depends upon the reason for publishing. It is never really necessary, but it can be a good tool if you want to get your company's name out there, keep your shareholders up to date on your progress, get more traffic to a website, or as recommended, to attract business deals, partners, investors.
If you do it, don't expect it to be huge news. There are literally hundreds of news releases every hour or minute every day. If you pay to use a service like PR Newswire, they can add value by adding SEO and targeted distribution to people who may want to read it for a couple hundred bucks.