lmutter - 9:52 pm on Oct 15, 2013 (gmt 0)
"A well-developed set of negative keywords can let you bid on broad and phrase match to catch wider exposure yet still keep a lid on unsuitable impressions and clicks" is VERY true. You don't want to limit yourself. Build a full negative keyword list and keep things on broad match/phrase match and run search query reports very often. Doing this will allow you to see what people are searching on and if they don't relate to you, add them to your negative keyword list. Lather, rinse, repeat :)
It is also key to have ads that relate to the terms in each ad group and a landing page with relevant terms as well. This will then lead to better quality scores and hopefully lower CPCs.
I've been in this industry for 8++ years, so feel free to ask more. :) Good luck.