It's called Shenzhen.
Lots of expats there. Most closer to the area called Shekou or Nanshan, but you'll find expats all over Shenzhen. The infrastructure is great nowadays, the Metro system works very well (I've used it just yesterday). Taxis are very cheap as well. You won't need a car, but owning a car is certainly much cheaper than HK.
what is the standard of living in Sheng Zheng?
Difficult to say, you have to go and see by yourself. We are all different. Yesterday I joined a (local SZ) friend for a nice pizza late afternoon, went to a good massage, went on to a (outdoor) bar where he usually hangs out, and met a couple of Americans, Mexicans, Swedish etc who fly for SZ Airlines. You'll run into lots of expats, often with kids and family, in the Shekou area.
Apartments are much bigger than Hong Kong, and much more affordable. But I guess you don't have to worry about this if your company takes care.
It's not America, they do speak Chinese in China, and you won't be able to get your favorite chips. You'll have to adjust and remember that you are in a foreign land.
typical cost of a sit-down normal meal nothing fancy?
My 13" pizza was RMB 98. Beers at the "Cheers" bar were 15RMB. My double espresso at Starbucks was RMB 17 or 18.
are buses/sub-ways pretty accessible?
Buses are no problem at all. I don't use them myself but I know American English teachers who do and they probably know their lines. The subway is a no-brainer, used it yesterday and it saves a lot of time compared to taxi or car.
Not sure how late they run, my guess is midnight or 1AM.
You don't need a car. My local friends have cars, but they know when and if to go by car, and they know their way around. For instance, my friend didn't pick me up at the place where I was yesterday, he picked me up a couple of subway stations away. Getting in there and finding a place to pick me up would have been just too trouble. For an expat, I'd say stay away from cars till you know what's going on. Taxis are cheap and everywhere.
is it a safe environment? or is it like every town; there are the ghettos and the upper class all mix in?
It's like the rest of the world. But it's a different world, so come and see.
What is Fu Tien like? Is it pretty industrial?
SZ is in general just buildings and big roads. Most factories are further outside. And people people people. You won't ever feel lonely.
Futian District - Wikipedia, the free encyclopedia
what is life like for a working foreigner there?
You don't have to live there just because you work there. You can live in Shekou or Nanshan. Live as expat will certainly be different if you live near the other expats (ie. lost of import food stores in Shekou).
Also check this site:
The definitive guide to Shenzhen, Shekou, Guangdong, China