It's a 4,000 x 4,000 map so it's pretty massive. If that one doesn't suit you, there are plenty more that are just as awesome if you search around a bit. They're an excellent canvas to build on and very inspirational. Heck, you could build entire kingdoms and civilizations if you really wanted.
That is amazing but at same time you probably shouldn't show a different map and tell them to use it when usually (not all the time) they want it all to be there own unique adventure. Not there's on someone's else's map.
@PsyBunnies: If you computer can handle it I'd recommend using world painter. It won't be as awesome as the guy linked but still a lot better than world generation. It's free, and easy to use. WorldMachine they also used I believe costs money but I've been wrong before.
or I have some presets you might like to use on the custom preset area, you might have to dig. But they are useful and has pictures. I hope this helps you.