After just over four months, Oink, the first app from Digg founder Kevin Rose’s new company Milk, will close its doors. The app was described as a ‘way to rate and rank the things around you,’ and billed itself as a ratings engine not just for places, but the things inside.

The app was downloaded some 100k times in just the first three weeks and hit the 150k download mark in just over a month. It will be shut down as of March 31st.

In a notice on the site, the Milk team says that its purpose as a company is to “rapidly build and test out new ideas” and that Oink was its first ‘test’. It has now decided to shut it down to focus on its next project.

Rose said in December that the service had over 40,000 active users and that it tracked “hundreds of thousands of Oinks” and “millions of sessions”.

The team thanks everyone who used the app and contributed their ratings and items to the database. The notice seems to emphasize that the Oink app was primarily about gathering data.

We are extremely grateful for all of your effort finding and rating the best things in the places around you. We’ve discovered thousands of awesome pizzas, pastas, coffees, teas… and roller coasters, zoo exhibits, paintings, sculptures, vistas… and sodas, salads, sliders, soups… and so much more.

This is an interesting case. A case can be made like the group designed, built and shipped a pretty slick ratings app all in a bid to gather data. Rather than mine existing databases or pay other companies to license their information, they were able to garner attention via the app launch and gather their own. And the data that they got appears to be more granular than most sites like Yelp or Foursquare.

Some talking points do rear their heads at this point though. With the quick shutdown of the app, will users be more gunshy about trying out Milk apps in the future, with the fear that their time will be wasted? If the app was indeed designed to act as a data gathering service, there is also the question of how users of the app will feel about that. Would anyone really be happy about their Oink data being repurposed in another app? Definitely things worth pondering for the Milk team now.

Of course, the app could have just failed to gain enough users quickly enough, and Milk decided to cut its losses and concentrate on something new. Fair enough and good for them for making tough decisions.

The team signs off with “So long and thanks for all the Oinks! More news from us soon.”

Perhaps we’ll be finding out just how the team is going to be using the data its gathered with its Oink test. If you were a religious user of Oink, you can enter your username or email address to download all of your data from the Oink site here.

We’ll be sure to ask Kevin Rose about his next moves when he is in Amsterdam for The Next Web Conference 2012 next month.