Congratulations!
Let me give you some advice on the Ph.D. route. Start collecting info on your topic as quickly as possible (and put it all in a reference manager, like EndNote from the beginning). Research the department and find the professors for you committee who will be helpful. Be wary of those with reputations of holding on to their students for many years. Any good advisor will want you to succeed, and do it quickly.
The most important part of grad school is finding your work ethic. Find the work schedule that is best, find the sleep schedule that is best and stick to them. Treat it like a job, and you will be amazed at how much free time you have.
Then use student loan money to travel the world! Once you get a job, you will never have the time to travel.
Good luck...and have fun!