In short: Google has lowered the price of the Pixel 2 XL to $699, that's $150 lower than it was yesterday, while the Pixel 2 remains at the same $649. Google is going to continue selling the Pixel 2 even though the Pixel 3 has gone up for pre-order now and will be shipping beginning next week. This means that if you were holding out for a Pixel smartphone, but were turned off by the big notch on the Pixel 3 XL or the pricing of either Pixel 3 smartphone, you can still pick up the Pixel 2 XL for a somewhat decent price.
Background: Typically when companies debut a new flagship smartphone, they will also drop the price of the last generation, and keep it available for a few more months. This is likely because either they still have a stock pile of them in their warehouses, or to give customers a lower price point to buy a new phone. And with Google upping the price of the Pixel 3 this year, the $699 Pixel 2 XL is looking really good right about now. Especially when you factor in the fact that the Pixel 2 XL is still beating smartphones that were just released, in the camera department. That right there is pretty impressive.
Impact: You can pick up the Google Pixel 2 XL from the Google Store for $699, and if you are on Project Fi, that might be the best place to look for your Pixel 2 XL. As Project Fi is still selling the Pixel 2 XL for $749, which is still $100 off of the regular price, but not quite as low as the $699 that the Google Store is selling it for. Project Fi also lists the Pixel 2 as out of stock, which could be why its price has not dropped. It is also quite possible that Google will not restock the Pixel 2, so that your only way to get your hands on one, would be to get a used one.