Today Canon USA announced they'll be offering instant rebates on many of their popular lenses until July 16th. The rebates are significant (none of those silly $10 rebates) and have already appeared at online shops like B&H and Amazon.
See Canon USA's site for more details, but if you have been thinking about purchasing a new lens, this is a great time to do it. Personally, I've been planning to get a Canon EF 70-200mm f/4 as my next lens, and now that they are $50 off (and listed at B&H for $530) a new lens is suddenly about the same price I'd be paying for a used lens. And I'd get a USA warranty with it. Cool!
The full list of lenses and rebates (and their current price after rebate at B&H):
70-200 f/2.8 L IS USM $1,600
100-400 f/4.5-5.6 L IS USM $1,310
85 f/1.2 L II USM $1,670
70-300mm f/4-5.6 DO IS USM $1,070
24-70mm f/2.8 L USM $1,065
400mm f/5.6 L USM $1,025
180mm f/3.5 L USM Macro $1,165
70-200mm f/4 L IS USM $985
70-200mm f/4 L USM $530 <= best telephoto price/performance ratio! 17-55mm f/2.8 IS USM $950 <= rich person's Tamron 17-50mm
17-40mm f/4 USM $630
28mm f/1.8 USM $375
50mm f/1.4 USM $285
60mm f/2.8 Macro USM (EF-S) $360 <= cheapest Canon 1:1 macro
I have no idea why Canon is doing this. Most of these are the higher-end lenses (maybe they're trying to boost sales?) too, but the discounts are close to 10% in some cases. If you were thinking about a lens, this is a great time to buy!
Personally, I'm going to do everything in my power to get the money for a 70-200mm f/4 USM before mid-July!
My birthday is coming up soon too (hint, hint) :)
[Update: I managed to get a really good deal on the 70-200mm f/4, so think of something else for my birthday. Like maybe a macro lens; I'd prefer a 90-100mm prime, but I'd take the 60mm macro if it was offered :)]