Rev, it's almost certainly a scam.
If you think of craigslist as a newspaper, you'll be ok; you find the listing you want, you contact the seller, the two of you meet up, you look at the item, you pay right there.
Steer clear of anyone offering to ship you something or, if you are selling, anyone who offers to send send you a check/MO and arrange for transportation of the item.
Please read these pages for more info and suggestions on how to avoid being scammed and how to "stay safe":
http://www.craigslist.org/about/scams
and
http://www.craigslist.org/about/safety