*UPDATE*
Apparently smaller retailers in the US have already been selling the lens, I guess they were allocated before the high volume web retailers. Thanks for letting me know.
B&H Photo has informed us that all preordered Canon EF 16-35 f/4L IS lenses will be shipping this week. We expect the same thing from other retailers in North America. Various retailers in Asia and Europe have already begun selling the lens.
Canon EF 16-35 f/4L IS $1199: B&H Photo | Amazon
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