Yes, Hopkins does have rolling admissions. If memory serves, the committee meets approximately monthly to issue acceptances and review applications under consideration. Some of my classmates were accepted as early as September, others as late as July.
I am pretty sure it is rolling because my friend got the acceptance phone call on his cell phone from the admissions committee as he was moving his stuff from Los Angeles to Albert Einstein to start med school over there. This was mid-August. You think those stories get exaggerated until it happens to someone you really know.