How much do I share with a writer about their submission?

After you send a book out on submission, how much do you let the writer know of what's going on?
It depends on the author. Some want an update each time I hear something from an editor, others don't want to know anything until I sell the book. I usually update my clients once every few weeks unless I have instructions to the contrary. As for the actual editorial letters, I typically will only share them if my client specifically asks or if they say something substantive.

Do editors call you up out of the blue with an offer, like a bolt from above, or do they generally keep you posted at each stage of the process?
Most of the time I'm kept in the loop, but on occasion I've gotten an offer in out of the blue. I definitely prefer being posted as things progress though, because I can then keep other editors who are reviewing the book in the loop.

Is there anything the writer can do - or not do - at this point that will make any difference?
Sometimes I'll have my client speak with an editor to make sure they share the same editorial vision, but usually there's nothing a writer can do. I suggest deep breaths.

Also, we all know when a book is on submission the writer is a nervous wreck, but what's it like for you? Just another day at the office, or does the anticipation get to you as well?
It's certainly not as nerve-wracking as it used to be, but I still get excited when I'm submitting a new project and I'm absolutely ecstatic when an offer comes in and I get to call my client.

Since this is the last question, I'll elaborate a bit more on that last point. In my opinion, the best part of my job is that phone call to a client telling them that they have an offer, and it's even sweeter when it's my client's first book. The second best part of the job is reading that project for the first time and falling in love and making an offer of representation. A close third is seeing that book in the store after years of sweat and labor.

I doubt these three events are ever as emotionally satisfying for me as they are for a writer, but because I have so many clients I get to feel these things over and over again. It's pretty amazing.