DsS has found a glitch that allows you to walk through any sufficiently thin wall and fall though any floor (nothing new there lolol), and another glitch that allows you to use the uppercut as a superjump to grab poles and such things. His summary from YouTube:
In order to be able to grab a ledge after performing an uppercut, all you have to do is one of these 2 combos in the air:
For 360, XXY or YYX followed by the jump button
For ps3, square-square-triangle or triangle-triangle-square followed by the jump button
In order to go through walls or the floor, you must perform the follwing combo, followed by guarding...
For 360, XYY followed by guarding
For ps3, square-triangle-triangle followed by guarding
The timing of your guard depends on what will happen. You want to guard when werehog finishes the spinning part of his breakdance like attack. If you time it correctly, you can go through most any wall. If you time it too late, you'll go through the floor (which can be useful in some places, but usually you just fall to your doom). Enjoy!^_^
Shamar night in 69 seconds. That's the most dramatic showpiece, but there's shortcuts and various interesting stuff in tons of levels.
edit: DsS has put the video up for the
Adabat hidden area. It's primarily a round chamber with platforms that rise with the water level as you reach each new platform and turn the switch, similar to Lost Temple or various Zelda puzzles, with the level's actual original goal ring chamber at the end - since he's actually in the ghost mission, activating the ring results in a failure message. The reason they cut it is pretty obvious once you watch it: while the platforms and the kill plane rise, the actual water graphics don't. My guess would be that it got left on the cutting room floor when time was short. It's a shame, as the concept is much more interesting than the rest of the level and the ring chamber is quite a bit more impressive than how they ended up leaving it in front of a barred door. Given that the engine capabilities for handling the area don't appear to have been implemented, I'd say that's fairly solid evidence against these hidden areas simply being reserved for DLC.