If you think you might want to teach, go for the Ph.D. now. You're at CMU and doing research (from your comments), so you can get some recommendations and possibly basically direct placement into top-tier schools. That opportunity goes away with years, as does the ability to live on ~22k/year.
If you want to work on the more researchy problems while in industry, also consider the Ph.D. Even the Master's is just a "quick pay grade upgrade" but won't get you into the research labs at MSFT, etc. You'll be just another hacker, albeit one with one additional line on their cv. Most of the graduate students I meet (in Computer Science) have no interest in being professors -- they mostly want to work in research labs or use the Ph.D. as a leg-up towards a CTO job.
If you don't care about either of those, go into industry.
If you want to work on the more researchy problems while in industry, also consider the Ph.D. Even the Master's is just a "quick pay grade upgrade" but won't get you into the research labs at MSFT, etc. You'll be just another hacker, albeit one with one additional line on their cv. Most of the graduate students I meet (in Computer Science) have no interest in being professors -- they mostly want to work in research labs or use the Ph.D. as a leg-up towards a CTO job.
If you don't care about either of those, go into industry.