I have been using Pinterest for years. But only in the past year or so have I used it for genealogy. Pinterest is a visual 'pin board' where you can save pictures and links. Many people use it to save cool pictures, craft related links, and recipes. But, it's also a great place to save bookmarks of all kinds. You can upload your own photos too, not just pin ones you find online.
One of the perks of Pinterest is that you can access it from anywhere. You don't have to have your computer with it's web browser bookmarks with you. And you can have as many different boards as you want, with any title or theme you want. You can repin the same link or photo to multiple boards as well.
Another great thing is the social networking. You can follow other genealogists, repin things you find in a search, comment on any of the pins, and even collaborate with group boards. With a group board you can have multiple people pinning to it with the same topic in mind. This is great for connecting to existing family or with other genealogists interested in the same areas of research.
Speaking of types of boards, you can make a board that includes a map. You can attach pins to specific locations on that map. This is great for family history. You can upload a photo (or pin one from the web), give it a description that pertains to your history, attach it to a place on the map, and basically create an interactive map of your genealogy complete with photos and links.
There are many genealogists on Pinterest already, even 'big name' bloggers like AnceStories and GeneaBloggers. If you search for "genealogy" you will tons of pins, which can be overwhelming. So be sure to click over to 'boards' under the search to find people with whole boards dedicated to genealogy of various kinds.
Have fun pinning (it can be addictive)!