Since Snow Leopard came out, we can have a 64-bit kernel on Macs that support it (which are not many), although we really have to think if it is something that benefits or hurts us due to the compatibility of our system, and if Snow Leopard comes with a 32-bit kernel by default it is for something, although I already told you that the 32-bit kernel is capable of running 64-bit applications perfectly, oddly enough.
- In favor: Faster access to system memory and a slight increase in internal speed for OS X management.
- Against: We lose compatibility with many extensions and programs that do not work with the 64 Bit kernel (such as Transmit).
I really think that 64-Bit is recommended for people with more than 4 GB of RAM that they want to always have maximum speed, but it must be clear that with the 32 Bit kernel we can run applications in 64 Bit since the only thing that will go in 32 will be the Kernel.
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