I’m not sure if this feature adds much to services that are already out there. After all, any company can publish its own blog; if it wants to send out shorter updates it can sign up for an account on micro-blogging site Twitter. Vator’s “Company Updates” feed falls somewhere between the two models. It looks like messages are limited to a 280 characters, which is twice as long as the maximum length of a message in Twitter, but much shorter than most blog posts. Vator users can “follow” companies, as in Twitter, and see all the updates aggregated on a single page, but you comment on each message as if it were a normal blog post.

Vator and the startups who have tested the micro-blogging feed say it offers a more interactive way to communicate. Many of the updates I saw last night tended to be a little more in-depth than what you’d find in Twitter, but much more digestible than a long list of posts. Plus, you’re probably communicating with a more startup-centric audience than you’d find on Twitter. It’s a small distinction, but the feed definitely enriches Vator’s offerings. And the site’s traffic has already been growing this year, according to data from Compete.

The San Francisco company is moving into a private beta test, which entrepreneurs can sign up for here. Ten startups tested the service already: Occipital, Nimbuzz, Blippr, Indaba Music, Crispy Gamer, Wize, Ignighter, Famplosion, Vayyoo, and Buzzd.

Vator raised an $1 million angel round earlier this year, following a round of the same size in 2007.

Speaking of Vator, the company also organized a mobile application contest with mobile advertising company Smaato. The two companies just announced that DialPlus, a San Diego startup that shows relevant information from the web before, during, and after a call, was selected from the more than 100 ad-enabled apps that entered the contest. As a result, the startup will get a free booth at the Mobile World Congress in Barcelona next year.