Actual CPUs will not change in price. Intel just releases new procs that (at least in theory) will have lower prices. That's how they've been doing it, even in the Athlon64 era.
You still find 3-4 year old CPU's on Newegg going for MSRP. It doesn't usually change until you have a used market to choose from, however the 7820X for example launched at $600 and is now purchasable for as low as $400.