I preferred to show up a little early. There was, indeed, a very loooong time -- but "Appointments Only" just three two people ahead of me. I got my call number, filled out a form, read for a few minutes, and at 2:47 I got called. After filling out another form and taking an eye-chart test, I was sent to the dreaded photo line. That was done, and I was out of the office a whole 10 minutes after my appointment was set for! (Even more so, because I live only about 10 minutes from the DMV office, I was back home just a bit over 45 minutes after I got in my car to head over.
I can't speak for other states, but if you live in California and need to go to the DMV office, I can't recommend highly enough setting up an online appointment. Easy as could be. Fast as could be. Now, I only have to wait until they send me a new license with a new, dreaded photo.