Speaking from experience here as a recent grad (BS in Math/CS in 2000, MS in Telecom in 2004), I was faced with that decision for a while, and seeing it in hindsight there is one thing you need to realize. The Masters is only going to get you into the door a little bit easier. It might get you to the top of the pile for interviews, but it by no means makes you a shoe in.
After that, you must deal with the fact that it's hard finding an IT company who wants to hire someone as 'green' as a new grad. Use your masters to get contacts in the industry, work your tail off to get a great summer internship if your program is two years long. I was lucky enough to go full time for two years, and wrote freelance for a well-known computer security magazine. Bolster your resume.
Use the masters to bolster your chances of convincing future employers that you are more than just a naive college grad.
Would you people stop playing these stupid games?!?!?!!!!