New contributions are visible in RecentChanges, you may assume that other contributors have noticed your appearance (if they are not complete beginners) but nobody cares to make contact. Are they impolite? Maybe there is a member that does WelcomeNewcomers, but he didn't show up? Nobody cares to fill the void? You don't know. It is polite to wait.
After 1-2 days you may assume that a SilentWelcome has happened and that you are now in the GuestRole.
SilentWelcome is an example for SilentAgreement.