The Polygon feature of Google Earth is what I like to use when I find family land. Its a great feature where no matter what the shape of the land, you can outline the property with Polygon. It's a great way to highlight an area.
Just like placemarkers they have a Name and a Description, however their name field doesn't show text next to the Polygon like placemarkers do. Back to descriptions, you can use this to add pictures, maybe you have a picture of the old homestead or the original deed. I am usually using the Bureau of Land Management to find old land grants and I use the land description in the description box of the Polygon. Then when you create the Polygon you have the visual and when you click on it the balloon pops up with the raw description of the land. Color coding your family land can be very helpful as you are plotting family land. If your family is anything like mine, families that stayed in one place for very long, eventually end up marring the farmers daughter next door, and color coding will help you identify the different family groups. You may also be able to identify other locations to research, if a family owns all the land around but not a certain parcel of land, maybe you need to look into why they didn't purchase it or maybe you haven't discovered ownership yet.
The visualization benefit to using Google Earth and the Polygon feature is amazing. Helping identify migration patterns, the community church they worshiped at, or even the local burial ground. I have even had to do research into a old coal mine that was on the property, but wouldn't have known if I never took the land description and actually plotted the land out.
Family Land isn't the only thing I use Polygons for in Google Earth. I use them in cemeteries and military projects I have created too, really anything where I am trying to highlight an area of interest. The cool thing google has done is you aren't restricted to a two dimensional outline you can make it three dimensional also and either have it follow the shape of the terrain or even float above the area you are focused on. Be on the look out for upcoming posts on how to make three dimensional Polygons.