I think 400 is up from the original limits.And the old modem days of tiny filesize limits.
(
Airman Gabber Living life like a 70's BBC presenter,
Thu 22 Apr 2010, 15:58,
archived)
you can probably track exactly when it changedby looking in anyone's b3tards account and seeing when the width of their pictures suddenly jumped from 280 to 400...
( boris the spider,
Thu 22 Apr 2010, 16:04,
archived)