At OCS the amount of PT you will be doing is fairly standard across the board, not including RPT sessions which I will explain in a second. You will PT Monday through Saturday for the first 9 weeks. Monday, Wednesday, Friday and Saturday are "run" days, generally you will have a "carrier run" (run on slightly hilly streets) on those days that is approx. 2.7 miles at a 18 to 23 minute pace depending on what run group you are placed in. On Tuesday and Thursdays you will be doing strength and conditioning training which is generally situps, push ups, pull ups, leg lifts, jumping jacks (known as side straddle hops), etc. for about 40 minutes to an hour.
During any of this PT you may mess some exercises up because everything is done as a group with "speed, volume, intensity" and may be punished by doing some RPT. RPT or "beat downs" as they are known at OCS is anything that your DI can think up to break people physically/mentally. Sprints, push ups, rest position (I won't ruin that surprise for you), standup-sitdowns, rifle exercises, pretty much anything under the sun that can piss a person off. When I left OCS the DI's were all about the "Insanity" workout program, so they are probably killing the Indocs with those workouts now.
Honestly I could write all day about what you can expect for PT/RPT in OCS, but it truly depends on who your class team is. For example my Class Chief loved Cross Fit, so when he wanted to beat us we did those workouts, which you can find on the internet. Bottom line is that the key to being successful is staying injury free and making sure you keep your form exactly how they want it at ALL times when doing the exercises. I trained for about a month before I left for OCS by working out 5 days per week running about 3 miles every other day, swimming the other two days about a half mile and doing push ups/various core exercises. The PT/RPT isn't too bad, but it does wear on a lot of people that are not athletically inclined/overweight/not willing to push themselves.
If you want a little taste of what your gonna get in OCS look at this video
. It was a very mild beating to say the least, but you get the idea. Good luck to those headed to Newport.