Often, women make the mistake of either defining or not defining their eyebrows. This has been the subject of some of my blog postings. Just recently, I was involved in a program providing one on one counsel for high potential women. The second most discussed topic was the appropriate shape and color of eyebrows.
For men it was completely different. Most men had thick eyebrows. I noticed that the thicker the eyebrow the more one became engaged and listened to these folks.
Also, look at some celebrities. For example, Chris Pine (he was recently in in This Means War) has these amazing eyebrows. They draw you in as he speaks. So, take a look at your eyebrows. Do they capture your eyes so folks are drawn in to listen to every word you say or not?