Yeah, I think it'll be a big deal! Apparently, Amazon and its 700 million round it led, agree there's a market.
The 400 mile version is a 180 kWH pack, and my guess is that will only come in the nicest trim and be over $100k. The 230 mile 105 kWH pack should be around 69k (after tax credit). If the cost per kWH for battery upgrade is the same on the model 3 ($280), then the extra 75 kWH would add 21k.
If I could wait and splurge on an EV, I'd wait for the Tesla pickup. Since I do a lot of road trips, the supercharger network is almost a requirement for me.