It depends where you do your editing - for me it's in CS3. All the adjustments in LR are neat and the GUI is sexy enough, but I'm really not interested in global edits. I prefer to select regions and make local improvements to key areas. The goal of the raw converter (for me) is to deliver the best, most neutral image which is primed for editing in CS3. If the goal were to open the raw file, apply a color/contrast scheme to the entire image and not edit specific areas, then I can see the appeal of LR. I don't work that way, so to me LR is just a really fancy can opener while all the cooking and seasoning is done elsewhere.
As Axel stated, the calibration file can be extremely important - it's removing sensor color cast. If your back doesn't have much color shift across the sensor, then this correction isn't as important. If a back has extreme shifts from left to right, trust me, the loss of this information makes post processing more complicated, time consuming - and downright upsetting. If LR incorporated this data, then I'd give LR a second chance. If I could select areas and feather selection, then I could probably due 50%+ of my editing in LR and in some cases there would be zero need for CS3. I imagine Adobe has already figured this out.