Yeah, keep in touch. Scotland isn't that far away.

In my experience, that keeping in touch stuff, without some real-world hanging-out time, doesn't work. One friend (in my whole life, it's been the other guy) loses interest and can't be bothered, and the friendship just withers and dies. I'd rather it didn't happen because it kicks you in the heart over and over until you realize the friendship is dead (and takes a tortuously long time if you're in denial), but I think it's a natural thing. You have to BOTH care for the long-distance thing to work.

You guys, on the other hand, don't live that far away from each other. Visit often enough so that you still are real parts of each other's lives, and start planning for that now.