A friend of mine got a visit from the USCIS inspector at his work. The inspector verified that he had a valid working space (cubicle) and even checked the pictures, frames in his cubicle to make sure it was HIS cubicle. This was an un announced visit. So expect this and as long as you are not in one of those H-1B scam consultancy you are okay. I think this was a required measure because of all the fraudulent companies specially of Indian origins.