I did order the refurbished model directly from Canon today. Like the other refurbished products I've gotten from them over the years, I expect that it will look new and that the optics will be perfect. I saved almost $300 compared to the full price at Amazon, even considering sales tax and their cardholder discount.
Amazon (today) $2299 less 3% Amazon card discount of $78 costs $2221 delivered.
Refurb $1839.20 plus Virginia sales tax of 110.35 is 1949.55. I get 1% back on Discover which is $19.50 so my total cost for a US warrantied lens is ~$1930.
I agree with the poster who said that the lenses that Canon sells refurbished are likely to have been thoroughly tested and repaired to actual factory specs than what you might get new. While most of the lenses I have purchased have been fine, I have had to return a couple of Canon lenses over the the years for exchanges. Heck, I went through three of the old 28-70 f/2.8 L's before I got a good copy, and it was good! Those lenses likely go back to Canon's service centers, are brought up to snuff, and sold as refurbished at a discount.