Good set of arguments by Plantinga against atheism, including:
1. The universe is "fine-tuned". However, I think that argument works strongly AGAINST those theists who believe in a miracle-working, science-sometimes-suspending God; the Earth is evidently NOT "fine-tuned" if we grant God the option of acting outside science.
2. If your beliefs are just neurophysiological states, or the obvious consequences of same, why should you put any credence in them? I think that's silly, since it sounds like saying "Computer memory is just the arrangement of magnetic and electronic states, so it is very unlikely to contain correct information."
3. The rebuttal of certain specific arguments for theism is not actually a disproof of theism. So you should be an agnostic rather than an atheist. While I concede that may have some force when one considers ALL theistic theories taken together, every SPECIFIC theistic theory I've ever known people to evangelize about has considerable disproof. The only theistic theories that I don't see as being convincingly disproved are the ones so vague and unimportant that nobody much cares if they're true. (E.g., the forms of deism that say God kickstarted the universe and has had no involvement since.)