I was having a discussion with a friend of mine about Gmail the other day. He told me that he tried to see the impact of placing the dot in the email address (i.e. the dot in “firstname.lastname@example.org”) somewhere else in the address (i.e. email@example.com). And he realized they all made it to his inbox. Obviously, I started playing with my gmail account, placing the dot all over my gmail address. Shockingly, whatever dot I places (or however many), all emails made it to my inbox!!
To be brief: john.doe@gmail will be treated the same as firstname.lastname@example.org, email@example.com, firstname.lastname@example.org. Very cool, this will prevent silly typos from preventing you from receiving emails.
More about this on Google support