The price is a steal, the seller gets featured in eBay’s Daily Deals, but the positive ratings (98,1%) are not stellar. Use your guts.
eBay seller bigvalueinc has a brand-new Canon EF 24-105mm f/4L IS USM for ridiculous $749 (click here) (original packaging). Free shipping and Canon USA warranty. Limited quantity. Usual price is at least $1050!
The sellers page is here.