Canon have just released the following information. Note that the mail-in rebates concerned are those related to PRINTERS and some VIDEO products. The current Canon instant rebates on Canon EOS DSLRs and Lenses are NOT affected. The rebates on DSLRs and Lenses are deducted by the retailer at the time of sale and no mail-in of forms is required.
Here is the latest information from Canon
Here's is Canon's earlier message: