I'm am thrilled with Lightroom. Let me explain why.
I committed to digital photography last Christmas with a purchase of a Nikon D70 and Photoshop CS2, then went on a month-long trip to Costa Rica, where I took 3000 photos. Then my job intervened for a while. But when summer started and I had more time, I kept putting off sitting down to work on my images, even after investing time in working through two how-to books, since PS was still just too intimidating.
So then I downloaded LR. It does 80% of what I want with probably 20% of the effort it would have taken in PS. Enough to get lots of images in final form. And with the confidence I have now developed with the tone curve, etc, I'm ready to deal with layers, dodging/burning, healing brushes, and all the rest. But I never would have gotten there jumping into PS cold.