I just noticed this tonight in Activity Monitor:

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Why isn't iTunes 64 bit by now? I would have thought with the release of version 10, that it would have been?

What's it doing that would benefit from the extra horsepower? If there's not much to be gained, I guess it's a lot easier to just keep it more backwards-compatible by keeping it 32-bit.

I believe we went down this road before , many times.

64 bit is memory addressing - nothing about horse power at all.

So having a cloud base delivery system, such as iTunes, then play back on ya machine - I don't think it will be any better then a 32 bit.

The more memory you can address... the more powerful your machine.

Think about it.

Not really
I mean, it is just more efficent - not more powerful.

Not that I want to get caught up in this, but I suppose it depends on your definition of 'more powerful'. To me it's contextual: for a particular given task, I think a useful working definition would be 'gets the job done faster'. So for audio or graphics or maths processing (for example), a true 64-bit application working with a lot of ram will be able to move more stuff around per second than one using only 32 bits, assuming the processor is up to the job.

In a non-processor-intensive situation, such as just playing music through speakers (which a 400MHz G4 with 512Mb of ram will do quite happily in iTunes) then 64-bit is superfluous, I think.

Correct - Pady
Yep depends on ones point of view.

Analogy if I can. Car engines.

You have a 240 horse power engine - throwing in a high octane gas, will make it run faster --> However the engine is still 240 horse power and certainly not more powerful, ya just fooled it or tricked it into thinking, its faster.

The basic limitation is a hard-drive one.
I think the hard-drive access of the library-size of iTunes is a maximum 4 TeraBytes, which, of course, is greater than the 32-bit addressable limitation of 4 GigaBytes.
iTunes is listed in System Profiler as being a 32-bit application, but this pertains mainly to the maximum RAM/virtual-memory-size of the running executable (assuming, of course, that one has a machine with that much RAM/virtual-memory, with room for the other apps and MacOSX Operating System to spare).
You really don't have all of the iTunes library loaded into RAM/virtual-memory at once.
Theoretically, 64-bits can address 18.44 (decimal) ExaBytes (18.44 quintillion unique combinations), but no one person has that much RAM/virtual-memory.
Even Apple's 64-bit executables don't use that full range.

I have to disagree with your analogy, carp - if you choose to use the word 'powerful' just to describe the rated horsepower of the engine (its measured ability to pull against resistance, a standard which is measured assuming a particular grade of fuel), then yes, that hasn't changed.

But the actual horsepower increases when you use a richer fuel - the engine can do more work with the same hardware when you introduce a richer fuel. It's not a trick, it actually happens.

*edit* Someone mentioned getting a Ferrari and only being allowed to drive it in 1st gear. I suppose the analogy here is that driving around the suburb of iTunes, there's no need to be going at 160mph, so top gear (or 64-bit processing) is irrelevant. It's only in places where you actually could drive the hardware that fast (such as maths/graphics etc. contexts) that it would make a noticeable difference if you could go into top gear.

While 64-bit memory addressing will speed up certain operations, like applying filters to massive Photoshop images, or encoding video, I'm not sure iTunes would benefit a whole lot from getting 64-bit. Hard drive speed has more to dow with those operations too.

I suppose if you were converting a ton of MP3s at once it **might** benefit a tad bit, but that really requires processor power and hard drive speed, not RAM power.