The Pixel and Pixel XL were launched on October 4th during an event in San Francisco along with a bunch of new Google products such as the Google Home Speaker, Google Chomecast Ultra, and Google WiFi. Speaking of the Pixel and Pixel XL phones, in the US, both phones were available for the pre-order from the Google Store, Verizon and Best Buy from the same day they announced. While the earlier pre-orders for both devices were expected start shipping from October 20th, now it appears that the majority of Pixel models are now either out of the stock or showing with 4-5 weeks of delayed shipping.
On the US Google Store, the 32 GB version of the Pixel phone is currently available for pre-order in "Quite Black" and "Very Silver" color options and shows estimated delivery date of November 23-25, while "Really Blue" model - which comes only in 32 GB version, and 128 GB versions of the Pixel are currently running out of the stock. On the other hand, those looking to pre-order 5.5-inch Pixel XL are completely out of luck as all the configurations in all color options are already sold out on the Google Store. It's also worth noting here that only Google Store versions of the Pixel and Pixel XL devices are running out of the stock or either showing delay in shipments, so in case you don't want to wait for such a long time or if the Pixel is not available in your desired configuration on the Google Store, you can still pre-order the Pixel phones from Verizon or Best Buy which don't seem to be suffering from such stock or shipment issues. On top of that, the Verizon version of the Pixel devices are not loaded with so much bloatware this time around and most of them can be uninstalled by the user.
Also, as earlier confirmed by both Verizon and Google, the Verizon version of the Pixel devices will also receive the timely system/security updates as soon as Google release them. But do keep in mind that Verizon's Pixel devices come with locked bootloader and can not be rooted so if you planning to install custom ROMs in future, be sure to pick your device from the Google Store as they feature unlocked bootloader and can be rooted easily.