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Some badges are awarded instantly (like the early badge awards designed to inspire a pavlovian reaction), some seem to be awarded in some kind of late night batch job (the harder to reach ones?) - is there any way of telling which is which?
So that if you are due a badge, there is a visual clue to suggest how long you should wait before yelling "where's my ^&%&%$(& badge!".
Perhaps a little icon with the letter 'i' in it, next to the instantly awarded badges along with a textual note at the bottom of the badges page would be enough.
ADDENDUM As noted below there appears to be a third badge timing, certainly for the 'Tenacious' badge.