Call it the end to a brief chapter in the Windows Phone saga. While there had been murmurs that the HTC Arrive was on its way out soon, any doubt has been removed now that the smartphone has vanished from Sprint's website and is likely on the endangered list at retail stores. The QWERTY slider's retirement leaves Sprint without any sort of Windows Phone in its roster, cutting the number of major US carriers backing Microsoft's platform down to three. Before you ask, we honestly don't know if the CDMA provider has a replacement waiting in the wings anytime soon: rumors of a Sprint Windows Phone 8 model surfaced as early as March, but the Yellow Swoosh network was nowhere to be seen among the Windows Phone 8 launch partners slated for this fall. The gap is conspicuous enough that Sprint subscribers may need a heaping amount of patience if they're not willing to switch networks for a Windows Phone fix in the near future.