I've always found it also depends on the airport. I used to have to do a lot of flying for work, and got used to the routine of taking off shoes/ stowing keys and watch in bag/ taking out laptop. At one time at Reagan airport, I had a TSA agent stop me after my computer bag went through the X-Ray. He hadn't seen a graphics tablet before, and he was being pretty nasty about why I hadn't taken the graphics tablet out with my laptop. This was one time in dozens and dozens of flights between Reagan and Atlanta. Other TSA agents are nice and if they're not sure what a lens is, they'll just kindly ask to look inside your bag.
It will be the discretion of the local TSA. Here in Atlanta, I wouldn't take out lenses: it's the world's busiest airport so they try to be efficient. In the past, when I've brought DSLR equipment, I've actually had discussions with TSA agents who've seen my lenses on the x-rays and say they'd like to get into photography.