When I first started reading this thread, I got nervous.
Don't be nervous. It's early.
15 anesthesiology programs, and I've heard from 7-8 of them. Dean's letters aren't out. Whole swaths of programs are just now sending out their first invites. Some people are still completing ERAS.
I'd agree with 10 interviews; you should be safe with that number. Then again, most people only go down at MOST 3-4 down their list. Go figure.
Best of luck; still waiting on Duke, Mayo-JAX, BID, BW, MUSC, UPenn plus a smattering of transitional years.