MP3 > Mac > N-Gage ?

You can always use a card reader if it doesn't work...

I dont see why not!
I havent seen any references in the n-gage manual for macs.
In theory though th n-gage will be seen as a removable drive and aslong as you dont have to install drivers for it (like win2000,winxp) and the os recognises removable drives easily. I cant garenty anything since havent tested myself and cant remember seeing any references to it in the n-gage manual.

I know this comes a little late but I have MAC and yes you can use the USB cable as long as you have a MMC card (blank one of course). I use MAC OSX versions 10.2 and 10.3. It just mounts the MMC card as an external harddrive.

So glad i was right about that!

So that me get this right, ghost-1. I can plug in an N-Gage (with a 128M MMC card in) and drag files from my Mac desktop onto the card, these MP3 files then play as normal with all the ID3 tag, etc?

If it operates as an external drive then yes!

Pretty much, you can do it with just about any kinda file. There about one or two hitches though. . . not big ones but ones that I think you should know.
1) Sometimes when transfering files a file with the same name is added with a prefix of "._" easily erased with Fexplorer or the MP3 player itself.
2) Sometimes when you drag, hit CMD-E, or hit the eject button to unmount the N-Gage, it doesn't. I haven't had any major problems but I did notice that sometimes when the N-Gage didn't unmount correctly the files I had transfered were corrupt. The computer pretty much gives you an error message letting you know this will happen. Easy fix, delete said item and just put it back on.

I have a Motorola T720, and the N-Gage's usb or bluetooth connectivity made it so I rarely use it. The only minus I have found with my N-Gage is that normal handsfree sets don't work. Since I didn't get the headset with my N-Gage I find it a bit fustrating.