We don't have any official word on this yet, but the above image (sent by GameStop employees to Kotaku) seems pretty convincing: The Xbox 360 Pro is no longer listed among the 360 offerings on the Arcade box on the right, leading many to believe the middle-of-the-road offering is being phased out.
You may remember that the Pro's death was heralded by Ars Technica's reliable mole back in June, leading us to hope that the second part of that prediction (irresistibly attractive Pro bundles) may not be too far off.
We'll keep trying throughout the day to get official word from Microsoft.