It's faster and smoother than the beta - I'm using win7. The Auto Tone is now fully calibrated (only exposure was modified in the beta) and the presets are calibrated to the sliders properly. I've not had any problems at all with editing, plug-ins, editing in PSE10 or CS3, etc. Although it might all be in my head (as no mention of improvements have been disclosed), I swear the sharpening functions are better than LR3. Perhaps this is a function of the other adjustments available in LR4 in combination with the sharpening routines.