I can't say how impressed I am with all the responses we got after the arepas video was posted yesterday! While it seems I got close, it was clear from the comments that I needed to make a few crucial changes. So, i made another small batch.
I used more water, so the dough was softer and didn't crack when I formed the arepas. I also didn't fry them, but cooked them on a dry (well, very super-lightly oiled) griddle. From the comments it was obvious this was a key, and after one taste I could tell why. It had a better crust and texture. Thanks to everyone who shared their knowledge!
Arepas Update 2.1
I just discovered these are killer grilled on leftover charcoal! Smoky, chewy, crispy goodness.