The replayability aspect may be the most important one given how important C&C seem to be in AP.
We're trying to show off a bit of this here, in that, behind closed doors, we're showing the same conversation with one character playing out in two different ways depending on Mike's actions, and talking a bit about the consequences of it. Of course, since there are different ways of playing through the game, there's some replayability right there (assuming you want to play through it once as a shoot-everyone guy and once as a stealth guy, or what have you), but there'll also be a bunch of storyline reactivity that will impact the game, so hopefully there'll be some incentive for people to play through it again right there. All I know is that I played through our E3 demo around 12 times today and it's still pretty fun.
We're saying 20-25 hours as an estimate. It does depend a bit on playstyle; stealthy characters will probably take a bit longer than people who run and gun.
is a demo going to be release prior to the release date