Craigslist Verified Accounts enable a Craigslist poster to:

a) post a particular Ad to several Craigslist categories and cities (cross-posting);
b) post numerous Ads the same day (multiple posting).
Craigslist Verified Accounts are required if you are going to post to USA and Canada Craigslist in Services section. Craigslist can also ask Account verification by phone for posting also to other sections, if it has found, that a particular IP or a range of IP-s is used for intensive posting.