Scott,
I'm not actually sure what you're after, but bokeh always depends on two things - aperture and focal length (angle of view). [ It depends on magnification as well, as Bobby pointed out, but there it's a question of what are you after - that bird 5 feet from you, or that child 50 feet from you. Bokeh is usually nicer when your point of focus is within about first third or half of your normal marked focusing range of your lens. E.g. from 3 feet to 10 feet on Sonnar 85mm f/2.8. If you want nice bokeh - get closer to the object or use longer focal length lens. The effect of bokeh will be different though between what you get on normal lens at 3 feet vs. short tele at 10 feet even at same magnification. For this reason I rarely think about magnification and am more concerned about focal length ]
In my personal opinion, bokeh always looks nicer on normal-to-short-telephoto lenses (from about 50mm to 135mm). Assuming of course we're talking about apertures from 1/4. to about 1/2.8 and no more.
I don't like bokeh on long telephotos, but that's because of the different angle of view (and perspective). And on wide angles it looks nicer than on long telephotos, but isn't quite close to the lenses in the range I listed above.
But then again, it's all a matter of personal taste.
Now, technically you can predict the way bokeh will look on the final photograph. Because as I mentioned, you know the aperture, you know the focal length and you know the distance. And it does come with practice
I'm sure there is a mathematical formula that would descrive the bokeh under different conditions, but personal experience is far more important
Mike.