I dont know if every GMail users are bombarded with spams but I am sure, my email address is known to every spammer.
I just made a small test and numbers are unexpected.
I get 1372 spam mails in 10 days !!! GMail need to improve upon spam attacks! I agree, they put almost all mails inside Spam folder but if they are sure that this is a spam attack why even delivering spams!! Windows live mail has extra ordinary techniques to fight with spam attacks!! I get 2 spams a month in my live account.