I'm in the middle of my two years off between undergrad and grad school. I definitely feel strongly that it was the best decision, and I'm glad that I'm doing it.
I heard from other people who advise against taking time off, saying something to the effect of, "It will be harder to go back to school once you've taken any time off". I disagree. I believe that time off will help with career clarification. If you are just going through the motions, enrolling in classes every year because it is the "next step", then it WILL be harder to return to school after some time off.
However, if you find that after a year off, you're really ready to get back into it, hit the books, and get going again, then you'll really know that you're heading in the right direction and doing the right thing.
Plus, I've enjoyed the break, enjoyed a relaxed 9-5 schedule (with nothing on my mind after 5 unless I want it to be
), traveled to Turkey, the Netherlands, planning one to the Dominican Republic (and back to NL!) explored new hobbies, got into biking, and re-visited old ones.
I've also had uninterrupted time to study for the physics GRE, which I've actually enjoyed and felt motivated for.