Unless he looked at a Coupe. The Coupe with NAV includes XM Radio. I noticed this when reading the Si Brochure that my son picked up. Here's something from the Honda website for the coupe.
EX with Honda Satellite-Linked Navigation System™
• Honda Satellite-Linked Navigation System™ with Voice Recognition and 6.5" customizable touch screen, digital audio-card reader and XM® Satellite Radio**


This is for the Sedan.
EX with Honda Satellite-Linked Navigation System™
• Honda Satellite-Linked Navigation System™ with Voice Recognition with 6.5" customizable touch screen, digital audio card reader.
• 160-watt AM/FM/XM Ready®†/CD audio system with six speakers
I wonder why (besides cost) that Honda did this???

2005 Honda Odyssey EX-L RES & NAV - Desert Rock Metallic
2006 Honda Civic Hybrid NAV - Magnetic Pearl
2007 Toyota FJ Cruiser - Black Cherry (First Toyota, Third non-Honda)