You can have multiple boards. I've created five to start: Beach House Decorating, for interior design ideas; Beach House - Dream Home, for exteriors and home plans; Books Worth Reading, for books I've loved and ones I want to read; Places I'd Like to Go; and Stuff I Find Fascinating. I may do two more in the new future for recipes and clips related to my work in Elder Care.
Another great feature of Pinterest is that you can follow other members and check out their boards. You can "re-pin" items from others boards to yours. And because you're browsing through other boards with the same focus, it's almost like having access to hundreds of magazines or idea books without having to flip through the advertisements and articles that don't interest you!
Check me out on Pinterest @ BeachHouseBooks.