It is my understanding that it is _really_ hard to see the difference between 8-bit and 10-bit delivery for real-world images
This is quite true. You probably won't notice a difference in most real world images.
Where you might notice a difference is in smooth gradient display on areas of continuous tone.
I have a Dell u2711 and a ATI graphics card + win7-64, all capable of 10-bits AFAIK (dont know about Lightroom).
Unless it's a FirePro card I don't think you'll be able to get 10 bit display to work. I tried with a Radeon card and couldn't get it to work, only the FirePro would do it.