In OS X I can unmount a TrueCrypt drive from Finder as it gets listed under the Devices sidebar. Now when I press Eject it's no longer accessible, however it's still listed in the TrueCrypt application - I can check the properties and dismount it.
Does the unmount from Finder provide the same protection as dismounting via the TrueCrypt application? If not what issues can I run into?
The way that I like to look at it is that the Truecrypt volume is like a device within a device. When you "eject" a device from a computer you are essentially telling it "Hey, finish what you are doing and stop using this device". When I was using my usb drive that was encrypted with Truecrypt, I had the same question - whether I could just remove it or eject it from one spot (Windows). The prevailing answer was that it is better practice to unmount it from Truecrypt so that Truecrypt could finish what it was doing and stop activley using the volume.
I have limited experience of using Truecrypt on MacOS, however I would say that you should eject it through Truecrypt. Simply ejecting the volume through Finder might close the front end of it, but since it still shows as mounted through Truecrypt it may not be secure.
At the bottom of this page it says to click Dismount to eject the volume and encrypt the data, so I would concur that the safest bet would be to unmount it from within Truecrypt.
Hopefully this helps you on your quest for knowledge :-)
