UCSD Geisel Library (named after Theodor (Dr.) Seuss Geisel and his wife). The views from the 7th and 8th floor are pretty sweet.

I started graduate school this Thursday at UCSD. I am in the Electrical Engineering Master's degree program, with an emphasis in Intelligent Systems, Robotics, and Control. My undergraduate degree was in Computer Science and to get a full understanding of the graduate level classes I need to basically take 2 years of undergraduate EE classes. I won't take that many classes, but at least all of the classes I'm taking this quarter are undergraduate courses. And although I have only had 2 days of classes, I am already swamped and wondering if I am ready to leave the familiar relaxed atmosphere of my current job and go back to school. Too late I guess.
So I had a meeting with my advisor and he suggested that I go for the Ph.D. degree (since I will have that option if I want) and put myself in that mindset right now. For those who don't know, I have a scholarship through the Department of Defense that will allow me to go to school full time, work part time, and still make my full salary. I get full benefits (retirement, health insurance, etc.) while I go to school. So for those of you who pay your taxes, thanks. I promise to make a difference in the world and use your money wisely. The scholarship will pay for my masters and my doctorate (if I so choose) and I will owe the government back 1 year for every year I am in school. Not a bad deal! Currently I am not extremely devoted to the subject and have that deep down desire to delve into one specific subject for the next 5-8 years. But I do like going back to school, I think I will learn a great deal, and am excited to do research in the field of robotics and write a thesis for my Master's degree. Although I am only planning on two years of school, I might like it so much and want to continue. That is something I will assess as time goes on. But I am still naive in the ways of graduate degrees and could use some sage advice. So my question to those of you who might read this blog and have opinions in this area is, should I go on and get a Ph.D.? What are the pros and cons? What do you think? What would you do if you were in my shoes?