'r.dewald' at gmail dot com is the same as 'rdewald', or 'rd.ewald', or 'r.d.e.w.a.l.d'
I got a rather warm and suggestive e-mail sent by a person who appeared to be from London intended for someone who seemed to live in LA about an upcoming visit. It was addressed to r.dewald at gmail dot com.
I looked up some help on that and I discovered they disregard the dots. Once you sign-up for email@example.com, u.sername, us.ername, u.s.e.r.name, and u.s.e.r.n.a.m.e become unavailable.
So, all you smarty-pants firstname.lastname@example.org users out there, well, your dots are meaningless, d.u.d.e..