Actually they are still in stock:
http://shop.usa.canon.com/webapp/wcs/stores/servlet/product_10051_10051_282307_-1
They are an even better deal when Canon has a 20% off coupon, but when that coupon hits the good lenses sell out within 5 minutes.
I actually purchased this one a few days ago without coupon, supposed to be delivered today, because I have to shoot a baptism in a low lit church this weekend. I'll see if I like it. If its a good copy, I'll keep it, if not, I'll either return it or sell it. Mine came out to be something like $1,203 with taxes. There's a free shipping coupon out there, I think it's SHIP712.