I haven't noticed that issue (G5 mac). Perhaps you could post a screenshot?
During the creation of this example I noticed that the cropped image has its pixels shifted by half a pixel which may account for the problem. The problem is obviously exacerbated when output sharpening is applied. As a matter of fact, it makes it simply impossible. Incidently, I was testing several DAM utilities and thus also RAW processors. It turns out that Aperture has an interesting halo problem as well. The same kind of edges as in this example show a rather large desaturated halo, no matter what setting of denoise or chroma blur.
I really like the rendering in LR. The smooth slider seems to get rid of the maze problem formerly present in ACR renderings, yet it retains fine detail better than DPP. I'll see if I can create an example later.
On the less positive side: I believe there is an over abundunce of sliders in LR currently. That needs to be seriously reworked. There should be one way to get a result, and that should be the right way. Now there are several ways to reach a result, and I think that a lot of people will have a hard time explaining the subtle differences between all sliders (if there are differences).
Another example: the saturation sliders. We only need a single saturation slider and it should work as follows: when + it should be vibrance, when - it should be saturation. Additionally, if +, it should simply follow a curve shape, not a gamma shape, this will eliminate the need for some esoteric "skin" color preservation blah blah...