Either this $1699 after rebate price is a hoax or B&H screwed up for a very short time. I tried to get in on this deal and it is no longer running. I called B&H and inquired about it and a rep named Joshua told me it is only a rumor, it's $1999 AFTER rebate.. not $1699.
Just wanted to put this out there. $1699 definitely worth it to me. $1999, not so much.
It looks like the $1,999 deal is off at B&H. Just put the lens in my cart and advanced up to the "Place Order" and it is $2,299. I did order mine a couple of days ago for $1,999. B&H did email me the $300 Canon mail-in rebate after I placed my order so I'm sure my final price will be $1,699.
It looks to me that there was a mini price war on this lens when Amazon dropped their price to $1,999 before rebate, B&H simply followed for a few days.
One thing I've learned over the years on camera gear, when there is a good deal, you have to react immediately.