Yes, these controls are most welcome. I have a 20mm Voigtlander lens that i use with my Canon 5D2, it is a fine lens but it does exhibit a lot of fringing at the corners especially on fine detail over overly bright backgrounds. I used to correct some of it in PS, but the new control in LR 4.1 is simply amazing. As an aside, my 21mm Voigtlander lens for my Leica does not need any such corrections, and does not distort. So to the LR team, thank you for including these controls.
Jean-Michel