That doesn't actually contradict what the guy I responded to said though; you'd want to try signing up for gmail with a few variations of your own login that have a few random extra '.'s. My assumption is that these would all be rejected due to the fact that the canonicalized version (all lowercase and with all periods removed) matches the canonicalized version of a currently registered login, but this guy was saying that's not the case.
You can also send a email to a gmail address with dots in it so sending a email to john.smith@gmail.com can be received by johnsmith@gmail.com, john.smi.th@gmail.com, etc. and vice versa.
