or Who should be scared, and who should be overjoyed by Twitter’s decision to compete with its eco-system.

Twitter announced on friday that they were acquiring atebits, the makers of the SUPER popular tweetie application for iPhone and Mac OSX. They were acquiring atebits for its technical staff and the products as well. This followed earlier in the week’s announcement of an official Twitter app for blackberry.

The main takeaway most people seem to be grasping from this is that Twitter has officially taken a shot at its own ecosystem. Sure on the surface it may seem like they are now competing against their ecosystem, but this does open the idea up for them making more acquisitions in their ecosystem as well. Trust me this gives the above-average developer a potential exit point, whereas before there was none if you were building for the twitter ecosystem.

If you’re afraid you can no longer compete with free, then remember this, twitter will likely have to monetize their properties soon. How they do it, we’ll see probably this week at Chirp, but they will likely extend this monetization to their handset/device offerings as well. More importantly though, if you’re building something better than Tweetie, then you can still make money from them. Start adding other networks to your toolbar, and you suddenly added value over what twitter is giving away.

Key takeaway: build something that ADDS to twitter, and you should prosper just fine inside the twitter ecosystem; build something that doesn’t solve a problem or add value, and you’re fucked.