As they say in boxing, styles make fights. Sure, Brock seems to be new at the sub-D game and so fighters adept at jiu-jitsu are likely to be favored.
Randy has used his wrestling to control his matches and now faces a bigger, stronger, and quite capable wrestler who isn't likely to be controlled so easily.
Brock has some unknowns. His cardio and his chin. Until they are truly put to the test he'll remain somewhat a mystery. If he's found to have great cardio and a solid chin his opponents are going to be in for a rough ride.
As for Affliction it's up to the fans. Do they want a competing MMA organization in the states? Are they willing to buy the PPVs to support it? Affliction did its part by going after fighters the fans want to see compete, but the fans need to do their part as well.
From where I'm sitting I'm happy watching the UFC and DREAM. Do I want Affliction to survive? Not sure if I'm that passionate about the situation. They have some talented fighters, but they have a long way to go before they get everything else running smoothly.