...I have a 17" i5 2.53 MBP, but am thinking of getting my wife a 15" i5 2.53 MBP, if I use CCC to clone/backup my hard drive, would I then be able to pop that backup drive in the new Macbook and everything would work? Or would I have to install everything from scratch because of different components, etc..?
The 17" Core i5 2.53 MBP & the 15" 2.4GHz or 2.53GHz Intel Core i5 MBP are both "Mid 2010" MacBook Pros. If we look at
the build versions that shipped with these two models, we find they have both shipped with the same Build numbers (10D2063a, 10D2094, 10D2101a, 10F2108) starting with 10.6.3 Build 10D2063a.
My conclusion would be that a direct clone onto a new Mid 2010 15" MBP will boot fine. Just use the
Combo 10.6.6 Update to bring it up to date if required, even it it ships with 10.6.5.
This is one of the joys of OSX.
If models are far removed, you can even erase the HD of the new Mac, clone your old OS to the new Mac (must be Intel CPU to Intel CPU OR PPC CPU to PPC CPU), then Boot the new machine with the bundled disks and the MacOS install will offer to "Upgrade" the OS.
In your case, however, a straight clone between the two models you suggest should work fine.
EDIT: Yes, migration assistant works too and most things are brought over, but not everything.
EDIT 2: Also, if you're upgrading the stock 320GB for a 500GB on the 15", see page 37 in the
User Guide.
Also note that the Mac can act like an external FireWire drive by starting it up in "
Target Disk Mode". When you boot up the other Mac, the first Mac's Hard Disk will mount on the desktop like a USB or FireWire hard drive allowing you to erase and clone to it.