you'll be fine, they obviously have confidence in you or they wouldn't have hired you. I'd do as you said, just sit back for a few days and ask alot of questions, listen to the bosses and the workers, you'll have a plan come together.
change is what it is, change, get's us out of our comfort zone for awhile....
i remember when stilleto started the current job, and how she had jack shit to do for quite some time, and how ridiculous it was for a while, and how little amity there was between her and her coworkers. good times.
good luck with your new job.
I'm sure it will be an exciting and possibly a little uneasy/slightly stressful time.
One thing ive learned is it really takes time to get an accurate read on new co-workers.
It takes some time for people to show their true colors whether in a positive or negative way.