Preheat grill. Drizzle fillets with olive oil, and season with salt and pepper. Grill for 4 minutes on each side, or until they flake easily with a fork. Remove from grill, and set aside. When slightly cooled, slice catfish.
Heat tortillas on the grill for 1 minute per side, being careful not to burn.
Assemble tacos by placing catfish slices on top of grilled tortillas; top with Jalapeño-Cilantro Slaw; then garnish with fresh cilantro.
For slaw, combine ingredients in a bowl, and stir well.