If you have many outbound links from your website does it hurt your ability to get better search page position and page ranks and so forth. What if you need to sell those links out the more advertisers you got?
Yes, too many OBL will hurt your websites in the serps. This is to prevent spam link sites and so forth, 100 or so OBL should be fine but 10,000 or so will hurt you.
Shawn stated somewhere that no-follow links will not help your site in any way, even if it is nofollow too many can still hurt your website.