A DJ cartridge has a shorter cantilever, technically speaking. This makes it stronger, allowing 'back cueing' and 'scratching'. Also, they are designed to track at heavier weights and give out a rather high output voltage.
I wouldn't call their features desiged for "abuse", though. Just different playing scenarios (dance/broadcasting).
A DJ cartridge is usually very well made. I am currently using a modded Stanton Groovemaster II (the stylus/cantilever assembly has beeen replaced for a Stereohedron line contact). This creature has high output, great bass, incredibly coherent midrange and musicality. A great performer, all in all. I've had no need to switch back to my Ortofon X5 MC...
Tom, you need to get out of your doomsday hideout and dance!!! :)