I read this info and lifted it from the game's site, some I had heard already but not all:
I. Game modes, additions, etc.
1. Pride Mode
- Wanderlei and Rampage are seen displaying their vintage Pride trunks
- Wanderlei walks out wearing a "PRIDE" shirt.
- Prime-looking Heath Herring and a prime-looking Mark Coleman w/ hair are seen wearing shoes.
B) Japanese Rules
- Knee's to a grounded opponent, soccer kicks and footstomps confirmed
- Elbows to a grounded opponent are illegal
- Rounds: 1st rnd= 10min, 2nd & 3rd rnds= 5 min
- Fights in PRIDE will be called by Bas Rutten and Stephen Quadros
- Pride fighters will have their Pride stats. As quoted from Wes Bunn, "Yes, all the fighters that fought in their PRIDE heydays will have their PRIDE stats
-Any UFC roster fighter can be used in PRIDE mode and vice-versa.
-Lenne Hardt will announce fighter intros
E.) Rope Mechanics
- You will not be able to pin an opponent on the corner posts
- Cannot soccer kick an opponent seated on the ropes (ex: Shogun vs Rampage)
2. Brands/ Sponsors seen
A) Seen from the first trailer
- Bad Boy, nutrabolics, xyience, Tapout, THQ, PRIDE.
3. Arenas/ Octagon locations
- Saitama Super Arena
- MGM Grand
1. Stand-up/ Striking
- Quick strikes will once again have the power to halt Strong Strikes.
- Revamped striking game.
- Quick strikes set up combo's easier and quicker than beginning with strong strikes.
- Head kicks will have greater effect this time around.
- Leg kick TKO's have been added.
- Leg check kicks have been added and legs can break from checked leg kicks.
- "Takedown Intercept" knees have been added to all fighters.
- Striking Feints have been added
- New KO animations
- Harder to KO someone than previous titles.
- Body Shot TKO's have been added.
D) Ground Striking
- Strong Strikes have the ability to interrupt transitions on the ground.
- More options to strike off your back have been added, inlcuding a clinched elbow or hooks
E) Rocked State
- The attacker has the ability to follow a falling rocked-opponent with strikes as he falls to the floor.
- The rocked fighter has the ability to "sway" away from the strikes of his opponent. He also has the ability to counter-grapple (RS/ R3 click)an attacker.
A) Positions/ Transitions
- More positions have been added, such as cage positions
- Offensively, you can transition from double-underhook clinch to standing back clinch.
- Defensively, you can punch your way out of a clinch. Navigation also helps. Navigating away helps release the clinch. On the other hand, navigating into your attacker closes distance and interferes with your attackers brutal strikes.
- Offensively, continuously striking your opponent "loosens your grip" and will eventually knock your opponent out of your clinch.
C) Ground Game
- Auto-Block has been removed.
- Wrestling sweeps have been added. You will be able to scramble into a "takedown motion".
- Machida tripping-takedown is back with struggle system.
- More takedowns/ takedown animations have been added for CAF (outside leg-trips, different single-leg and double-leg, jumping scoop takedowns to side control)
- Double-underhooks inside leg trip takedown has been added.
- Instant counter-takedowns are reserved for countering strong strikes. Countering a weak strike would initiate a struggle animation.
- The "shine" is still used for takedowns.
3. Submission System
- Standing rear naked choke, flying scissor heel hook, standing guillotine and mounted gogoplata have been added.
- Using the cage to set-up submissions (ex: kimura, guillotine, kick-off-the-cage armbar & triangle, etc.).
- Transition blocking ALSO blocks submission attempts
- As quoted from Kotaku, whom have had hands-on time: "UFC Undisputed 3's submission system looks vaguely like the one introduced by EA Sports' attempt at an MMA game, with submission holds spawning a mini-game played on an octagonal graphic interface. That submission game is a cat and mouse-style chase, with the dominant fighter attempting to chase down the submissive fighter. They're represented on the edges of that octagon with a small dot for the submissive one, a larger, but ever-shrinking line for the dominant one. Catch the dot with your line and your opponent will tap out."
- The "shine" is gone for submissions
4. Cage Mechanics
- Defensively, you can wall walk off the cage.
- New cage positions have been included, such as the SEATED cage position w/ variants (open guard seated & half-guard seated)
5. Fight settings
A.) Simulation Mode
- No open weight fights. Some fighters will be included in other weight classes, but not all fighters.
- Added "Competition Spec": this apparently gives the ability to turn off all random effects during a fight (Flash K.O's, Doctor Stoppage, etc.)
- "FINISH THE FIGHT" has been added. Apparently, you have the ability to continue to strike once your opponent has been K.O'd. It is an optional ability.
- STAT breakdown (damage analysis) after EVERY fight.
- Harder AI with the addition of a new, harder difficulty known as the "Ultimate" mode. AI will use feint attacks and transitions
- Featherweight and Bantamweight have been added.
- Over 150 fighters
- Fighter entrances are added.
- Two gameplay control options, traditional and simplified.
- Stat decay removed in Career Mode.
- No Super CAF's(create-a-fighter).
- Fighters WILL not have the ability to pass out or not tap.
- Between rounds, recovery of damaged body parts has been increased to promote a longer, more competitive fight.
- Corner man audio has been confirmed. During the fight, you'll be able to hear your corner shout out instructions.
- Mirror matches are confirmed. This allows players to choose the same fighter in a fight.
- Cornerman are more accurate and precise with their advice/ feedback towards their fighter.
- More thorough tutorials, including standard tutorials (about-the-game tutorial) and middle-of-the-fight tutorials and interval advice tutorials.
- High-profile fighters will be recieving special attention (ex: unorthodox strikes, movements, etc. like Jon Jones, Clay Guida, Dominick Cruz)
- In "Finish the Fight", the knockout will ragdoll your opponent but "blend" into an actual position where you will be able to finish him with repeated strikes until the ref physically pulls you off.