Terry
For a bunch of reasons I have stuck with Lightroom including the new 2.0. I still find much to like, but the plug in architecture of Aperture 2.0 is now beginning the segue to a new tool. I now have used demos or real versions of Silver Efex, Vivenza, Dodge and burn, etc and they just make the raw converter the stop of choice. For the most part you can get the final product almost right before going to Photoshop for final local adjustments. Really nice workflow.
All Aperture needs is a clone of the retouch brush from Lightroom to be a killer App. The retouch tool in Aperture, at the moment, is too lightweight to be considered against the Lightroom tool. Lightroom has the ability to brush sharpeness, clarity, saturation etc etc so that you have local controls that are unmatched elsewhere. But with the open architecture of Aperture, someone out there will produce the needed tool, I am sure.
Aperture will be declared the final winner, of that I am sure
Woody