Blogging and sharing company Posterous has announced via its company blog that it has been snagged by Twitter in an apparent ‘acqui-hire’, with Twitter interested mostly in the people, not the product. Various Posterous engineers, product managers and more will join the Twitter team and the existing ‘Spaces’ that users have will remain up and running for now.

This is all despite Posterous being emphatic just 19 days ago that it had ‘no plans to sell’.

Twitter says that it will give users ‘ample notice’ if it is going to make any changes to the service. We’ll take them at their word on this one, but if I was someone running a personal blog on Posterous, I would think about finding another place to host it soon.

In its own announcement, Twitter says that its acquisitions of ‘people and technology’ have enabled it to make the service better. We’d read this to mean that you’re likely going to see the service being shut off after a grace period of some sort. Twitter even states that if users would like to back up their content or move it, that they will share ‘clear instructions’ on how to do so within the coming weeks.

The team at Posterous is indubitably talented. Posterous founder Sachin Agarwal is a former member of the Final Cut Pro team at Apple, where he worked on the product for 6 years before leaving to form Posterous. Today’s acquisition brings in the biggest ‘new hire’ class at Twitter yet, with over 36 people joining the company.

Agarwal says that “the opportunities in front of Twitter are exciting, and we couldn’t be happier about bringing our team’s expertise to a product that reaches hundreds of millions of users around the globe.”

He also emphasizes that Posterous Spaces will remain up and running “without disruption” and that notice will be given to current customers if any changes are made.

Agarwal adds a note to the users of Posterous, especially those that have been with the service for a long time. “The last four years have been an amazing journey. Your encouragement, praise and criticism have made us better. Thanks for that. We look forward to building great things for you over at Twitter.”

Twitter has followed up with its own post about the acquisition, emphasizing that its acquisition is very much about the people behind Posterous:

Today we are welcoming a very talented group from Posterous to Twitter. This team has built an innovative product that makes sharing across the web and mobile devices simple—a goal we share. Posterous engineers, product managers and others will join our teams working on several key initiatives that will make Twitter even better.

Posterous has also created an FAQ document for those with questions about the service:

What happens to my Space? Will Posterous eventually shut down?

You can use your Space(s) exactly as you have in the past. We’ll give you ample notice before any changes or disruptions to the service and we’ll provide specific instructions for exporting your content to another service. Can I still post to my Space?

Yes, you can continue to post via email the Web or our iPhone or Android apps. We’ll give you ample notice before any changes or disruptions to the service. How can I backup or export the content of my Space(s)?

We’ll share instructions on how you can backup the content of your Space soon. What happens to my content if I don’t do anything to my Posterous account?

We’ll give you ample notice before any changes to the service and we’ll share clear instructions about how to move your content to other services. In the meantime, your Spaces will remain up and running without disruption. I bought a custom domain from Posterous – what happens to it?

Our domain partner, eNom, will take over domain management. Over the next several days, you will receive an email with instructions for accessing your new domain account. I am redirecting my domain/subdomain to Posterous – what do I need to do?

Your domain or subdomain will continue to point to your Posterous Space. You do not need to change anything. Can I export my Space’s to WordPress, Tumblr, Blogger, or another service?

Over the coming weeks we’ll provide you with specific instructions for exporting your content to other services.

Posterous has a loyal following among those who frequent the service, and has a long history of interoperability with other social networks. It was a pioneer of the ‘cross post’, which allowed you to make one post to your Posterous Space, which then automatically appeared on Facebook, Twitter and other sites.

What Twitter will be using the acquisition for isn’t clear, but if I had to guess, it might be to help it build a curated news platform out of its new #discover tab, or perhaps to assist in creating its own ‘tweet longer’ service. As Twitter moves to welcome new users with a shallower technical base, it needs to create ways to display content outside of its traditional ‘140 character’ formula, without upsetting the apple cart for existing users.

There is also that aforementioned prowess that Posterous has with sharing media from service to service, something that many users love Twitter for now and likely something that it could be looking to improve. Or perhaps Twitter simply wants to refine its new brand pages and thinks that the Posterous team is the right fit.

Whether the acquisition was to build a specific product, or just a ‘cheap’ way to hire top talent, it seems likely that it feels that the Posterous acquisition will help it do just that.

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