I applaud Toyota for taking the Land Cruiser back to its roots. I also have my eye on the GX550 Overtrail, and it's the one I'd choose between the two. The 4Runner is left in an odd spot; it will be updated, but where will it land? It has always been the go-to 4x4 SUV for people who can stomach rental car quality but demand dead-nuts reliability. Toyota kept the 4.0 V6 alive in the 4Runner after the Tacoma because it needed the added grunt. My dad loves his new Tacoma but I find it's 3.5 lacking down low compared to the earlier 4.0 trucks I had driven. I'd say that suggests Toyota will offer something beefier in the 4Runner, but manufacturers are loving these turbo 4/mild hybrid combos.
Honestly though, as knee-jerk cool as some of the newer stuff is, I snap back to reality when I compare any shiny new thing to the LR4. Yeah, LR4s have their problems an the newest ones have a gross shift wheel and lame V6. The nicest V8 ones cost less than 30K these days. The interior puts new cars to shame and they're 90% as capable as any of the new offerings. Also, it's a V8! I know for a fact it will destroy a newer GX460 in a race. Timing chains, pipes, and control arms are costly, but they're not going to make up the $50K difference. $75K will get you a V8 supercharged 2019-2020 L405 with a 5 year extended warranty. I'd be more inclined to go that route before I dropped it on a rental car.
Lexus came out of left field with the IS500 in a time where even Dodge is retiring V8s. If they put that engine the GX550 I'd be really tempted.