The trailers have focused a lot on the "running after mobs" thing, which might indicate that there is a lot of it -- but it's already boring/gimmicky. Actually, most of the gameplay mechanics/systems feel kind of gimmicky. The way certain objects might highlight in fights, the costume/items for rep system, even the way they've portrayed the cover/slide mechanic.
But I guess most systems in games might feel gimmicky if they were hightlighted like that -- many are as well, I guess, but are still a lot of fun if they are integrated right.
Anyhow, I hope the world is large enough to explore for many hours, or specifically, diverse enough. I really hope there are some large forest areas with some fun gadgets -- there was a forestish area in the trailer, but no idea how large it is.
Sleeping Dogs’ open-world to have “gameplay density,” instead of size
United Front has said not to expect Sleeping Dogs to be quite as large as previous titles in the True Crime series – the franchise it was originally developed for.
Speaking with OPM, design director Mike Scupa said the team focused instead on “gameplay density,” and an “environment that really catered to the strength of our gameplay”.
“A large portion of our game takes place on foot and our driving is very action based,” he said. “We really wanted to focus on a very streamlined and gameplay centric world layout.
“We really tried to pack the island with many different kinds of stuff as possible. I think our size is fairly competitive with other open world titles.”
“Your character is very powerful, an action hero where you can do all these things [so] we didn’t want you to have to go too far to be able to do those things,” added senior producer Jeff O’Connell.
In other words, it may not be as large as, ohm say San Andreas as an example, but there will still be plenty to do and see.
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http://www.vg247.com/2012/06/29/sleeping-dogs-open-world-to-have-“gameplay-density-instead-of-size/
Before Square Enix got ahold of it (I think they were still with Activision.), I think I read that the world was supposed to be massive, and exploration was a very important element or something.
Maybe Sleeping Dogs will have a much more detailed, complex and interactive game world, but it does not seem like it from the trailers. If anything, the game world seems to be less interactive than Saints Row/GTA...
And on the enviroment object combat; I read a preview where the guy playing it said he was skeptical about the system, but apparently the enviromental objects are all over the place (I suppose the preview implied that despite the fact that the objects are random and placed throughout the world by the developers, there are so many of them that you can somewhat rely on them.) and are also very diverse. (50+ uniques?)