Sharp and a great value at $350. On a 1.6x crop body (e.g., 20D) I still prefer the 85mm f/1.8 and 35 f/1.4L, but the 85mm can be a little tight indoors when you want more than a head shot. The 50mm comes in handy in these cases. I've had occasional auto-focus issues with this lens on the 20D (as others have reported), particularly when not shooting up-close.

Since I moved to a full-frame 5D with its wider field of view, I've sold this and use the 35/1.4L and 85/1.2L II mainly, and note that 85mm on a 5D has about the same field of view as a 53mm (85mm/1.6) on a 1.6x crop body.

Canon released a 50/1.2L ($1600) in Nov/2006. So far, reviews have been a little mixed but the general consensus is that it's not as good as the 85/1.2L. Auto-focus reliability, sharpness, and contrast - compared to the 50/1.4 - seem to be a little disappointing given the price, but other reviews indicate the opposite. I'd like to see the price and the reviews settle down a little more. It would be nice to have the 50/1.2L as my 35/1.4L can sometimes be too wide on a full-frame camera, particularly for adult subjects.

I recommend the The-Digital-Picture.com for comprehensive reviews.