So now we know that Martin was beating the crap out of Zimmerman, has the injuries to prove it, was calling for help at least 14 times, and Martin was using drugs.
We also know Martin was suspended from school three times, including once for having drug residue in his backpack. Zimmerman was actually correct to be suspicious about this kid walking through is neighborhood. He actually was a thug.
Martin didn't commit a crime by walking through the neighborhood, but Zimmerman didn't commit a crime by "profiling" and following him either. Comes down to who started the confrontation. Unless Zimmerman swung and missed to start it, it sounds like Martin was the aggressor.