I'm 99% sure it is. The 7,500th was on September 28th, 2011, and I know that one was really #7500. A little over 2.5 years is about right.
They've been very good at having the "x,000th's" and "x,500th's" fall on the right show. For a while, their own count was off by 145 episodes (the "7,000th" was actually show #7145), but to the best of their knowledge, the milestones have been celebrated on the correct date.