I think so much affects a shot's bokeh that its not entirely fair to lay all the blame on the lens. Of course, the lens's maximum aperature and diaphram shape and front element's shape have a lot to do with what characteristics of that bokeh CAN be, but ultimately a lot more is involved in the final product. Subject's distance to the background items, contrast of the subject's colors to the background's colors, busyness of the background (and foreground, bokeh can occur with items in the frame that are outside the DOF while being in front of your subject as well).
I don't think the Canon 50/1.4's bokeh is bad. Of the AF 50/1.4s they are all about the same. I find the 50/1.4's bokeh pretty smooth and creamy... sometimes a little too much so. I find the bokeh of my Zeiss 58/2 to be much more appealing these days, but I recognize that what appeals to me most about that lens is the contrast and colors, with bokeh coming in 3rd place (with sharpness, which is amazing, in 2nd place).
I have a Helios-40-2, the lens that is sometimes known as the "swirlios" because of its truly unique bokeh which seems to make like a kitchen sink drain and swirl. Some people hate this effect, I find it very interesting.
Bokeh is a personal preference, and for people to spend so much time **** and moaning about some particular lens having good or bad bokeh is kind of missing the point. The lens has to be a lot of things. It has to be sharp where you want it to be, it has to have colors and contrast that represents the scene you saw when you tripped the shutter, and it should handle the background (if it is far enough to separate) with care up to its abilities. If I ever start hearing about how some f/4.5-5.6 lens has bad bokeh, I will call up Chuck Norris, give him their address and ask Chuck to give them a roundhouse kick to the head. 
I'm including a shot of a face in the crowd at a Yankee game I went to this fall. Shot @ ISO 400, f/4, 1/200 ... 40D + 70-200mm f/4L IS USM @ 200mm. Minimal processing, Brightness +50, Contrast +25, Blacks 2. I like the bokeh of this shot, I feel the person between me and the subject being out of focus gives the shot more dimension - others may not agree. Feel free to chime in.
-Alan
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