The Groupon acquisition of CityDeal is being hailed by many across Europe as a good exit for the German-based clone (yes, there is no point in saying it is anything else but a Groupon clone). But luckily there are more than just clones in Germany. The burgeoning cluster in Mitte, central Berlin, is producing startups such as Soundcloud , hiogi , Babbel , Twinity , SongBeat and aka-aki . Nokia bought Dopplr and with it set up an innovation lab amongst the beating heart of Berlin's startups. Hamburg has spawned many others include Qype , Europe's Yelp, and more recently the interesting Apprupt . VCs in Hamburg and Munich vie over raw engineering talent out of German universities, and our TechCrunch Europe Munich and Berlin events last year were buzzing. As US-born Germany-based VC Paul Josefak recently guest posted for us, he's coming across "multiple companies who recently closed either initial or follow-on rounds." Berlin is now vying with London as the second tier cluster in Europe with a decent critical mass. But there are clouds on the horizon, and they come in the shape of an attack of the clones, if you will, or more accurately, Pollution of the Clones. While the market for copycat businesses aping the latest startups form the Valley is well known, it's been a component, but never the only aspect, of the German scene. With Groupon's acquisition of CityDeal the Clone Scene could now threaten to overtake it's younger brother, the Innovation Scene. Here's why.