This is a fantastic lens for the right photographer.
Check out the review here:
http://www.the-digital-picture.com/Reviews/Canon-EF-70-200mm-f-4.0-L-IS-USM-Lens-Review.aspx
This lens retails for anywhere from $1200-$1500 new, and this lens is still in "like-new" condition. Only reason for selling is that it isn't being used as much as it should be.
Priced to move!
Email to come see it or if you have any questions (I'll do my best to answer them.)
Send me a phone number and I'll call or text you back ASAP.
Thanks!