Mac installation disk
The restore disk only works with your specific system, but does it contain all required systemfiles for all previous macs (like a retail dvd), or are they stripped from it?
There are two basic differences with the system bundle discs and the retail discs: contents and installation restrictions.
The bundle discs contain all the generic stuff as well as things that are required for the new hardware, providing necessary hardware drivers that may not be in the currently-released version of OS X. A good example of this would be 10.6.3. The retail version will not run the newest Mac Pro models, though they also shipped with 10.6.3 - just an extended version that contains updated support software.
The retail disc is generic and will install on any Mac made before it was released (assuming installation requirements are met) but on bundle discs the installer is generally locked to the hardware it shipped with. The installer will refuse to run on hardware other than what it shipped with.
Once you have the OS installed, the next system update brings all the software up to parity. In the 10.6.3 example before, installing the 10.6.5 update on the resulting drive gives you a system that can boot any current Mac, the new MacBook Air included.