If you link your blockchain.info wallet with gmail, it becomes extremely difficult for the hackers to steal your coins. If you can activate the Google Authenticator, then you can be 99.9999% sure that no one is going to hack your wallet.
That is right, there are a lot of ways to make your account secure, after that the safety of your account will be in your hands because it is super safe in that wallet. But still, we know hackers find their way to steal money or bitcoin, or other currency to people. If they can't do it in codes, they will do it on talking, so we must be still careful.