Not my petition, just thought it was interesting. Here is the latest word from Grubbs Infiniti (a reputable source) regarding this matter:
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"There has been much discussion regarding this issue but this is how it stands. All vehicles that were manufactured starting in March are prewired and will accept either Sirius or XM kits that will be available starting at the end of April.
For those vehicles that are not prewired there will not be a kit available.
BUT WAIT!!! The radio head is SAT ready (if it has a SAT button) and of course there will be replacement parts available for those vehicles that are prewired. If someone was to purchase those replacement parts and install them on their car that was not prewired then the new kits would work perfectly.
That is where we stand."
- Souce: FreshAlloy, DFW_Infiniti</font id="blue">
Basically sounds like if your car was built in or after March, all you need for Sat radio is the XM or Sirius kit (receiver and antenna). If your car was manufactured prior to that, you'll need a wiring harness to connect the kit to your head unit. Doesn't sound like a big deal either way, as a harness can't cost more then $20 bucks!
2003 G35 Coupe (on order)
6-speed
Diamond Graphite / Graphite