Magpie, one of the first ad bidding networks built entirely around Twitter, is now up for sale. Turns out, the team has decided to move onto bigger and better things. Two years after launching, the European startup is looking for an exit. CEO Jan Schulz-Hofen explains in a blog post,

We have decided to sell the company in order to focus on this idea, and we’re taking offers now. To make this very clear: we know that we have only seen the dawn of social media marketing, and we continue to believe in the huge potential of Magpie. To any buyer who understands online advertising, Magpie will be of enormous value. If we do not get a reasonable offer by someone who is willing to take good care of Magpie, treat our twitterers and our advertisers with respect and provide great customer service, we will continue to run Magpie. Putting it up for sale does not mean that we do not believe in the idea anymore; we just don’t want to do nothing halfway.

For anyone that’s been paying attention to the Twitter climate, advertising is big business around the microblogging service. While startups have launched a myriad of advertising services around Twitter, figuring the ins and outs of monetizing this specific type of social activity has been a growing challenge, even for Twitter. The relationship between consumers and brands, twitterers and market researchers has been blurred in a swirl of micro-brewed messaging.

The past year has brought a wave of new products and features directly from Twitter, validating the marketing prowess around its network. The emerging data exchange networks that seek innovative ways of improving targeted marketing via Twitter have further proven the worth of its network as a marketing tool. Whatever the Magpie team has up its sleeve must be good, and possibly unrelated to running an ad network. Some entrepreneurs are more interested in building than maintaining. Here’s some stat candy from Magpie’s last 30 days:

– 4,704 registered advertisers with many European and U.S. brands, agencies and smaller businesses
– 19,864,624 followers combined reach from a thoroughly vetted twitterer user base
– 116 actively running campaigns
– 14,852 Magpie tweets served
– 21,286,338 ad impressions

Click here for more details on Magpie.