I think the final 4 fire making will either be hit or miss entertainment-wise. The first two times it had some excitement to it, but this season it was kind of dull because I think everyone knew Nick would beat either Mike or Kara. I think it will be here to stay for a few more seasons at least, but I think it could get old pretty quickly, and they might have to come up with something new. I'm not a huge fan of it. Honestly, making fire is much less exciting when you know it's coming. When it's because of a vote, it's much more entertaining, such as in Worlds Apart.
Also, I wish they would go back to having the final immunity challenge be an endurance challenge. It's less about skill/talent and more about will power. I'm tired of this ball in the tracks challenge. And these giant mazes and structures. I want to see they battle it out through uncomfortable conditions. But I also am a huge fan of endurance challenges. My favorites are the ones where they have to hang onto a pole, hold their hand above their head with a bucket of water chained to their wrist, etc.