It's not "canceled" in the same way that other shows are. There was never an intention to tell much over 100 episodes, and you can understand why if you think about the fairly short timespan between Episodes 2 and 3. While it is a conflict that is waged over the course of years, it's not something that you can over-fill with stories because it just wouldn't make sense.
Also, there's no way that the remaining episodes DON'T get picked up by Disney XD (Disney's kind of teenage/tween channel that has other more "mature" shows). I think that was the plan all along.
Don't worry people. They'll finish out the Clone Wars series with a bang. We all knew this day HAD to come because we knew that the war would have to end at some point.
I'd rather they finish it while we're still hungry rather than us begging them to stop. I cannot say enough about the job that Dave Filoni and his team have done. It took a while for me to get into the show, but once I did, I realized that he and his entire animation team have an absolute love for the franchise, and they put a lot of effort into making it live up to standards (though, they'll never please everyone - just like George couldn't).
What an incredible series...I can't wait to see what happens next!
If I die today, I'm happy how my life turned out