As a creative agency who run a multitude of email campaigns on a daily basis for our clients, my first reaction was one of joy, on hearing that Gmail were making it much easier to unsubscribe from an email through the introduction of a prominent unsubscribe button next to the senders name.
On a personal level, I hate the amount of time and effort it takes to unsubscribe from emails that you never knowingly asked to receive. I always end up being frightened that the unsubscribe link hidden at the bottom of the email (if at all) that I have to press is actually a virus just waiting to be unleashed on my computer.
At a creative level, I think this will help advertisers improve their game in terms of the timing and relevance of their emails. Those that pass the test will be read, those that do not, will forever be confined to Room 101.