Happy for the Sparrow folks, not so happy for my fellow users and me. I am using it since the beta and they kept promising from that version on that they would

Happy for the Sparrow folks, not so happy for my fellow users and me. I am using it since the beta and they kept promising from that version on that they would add the one missing feature for me (and a dozen of other users): undo support. I stopped using Sparrow for this only reason; then at 1.6 I started using it again; just to see where it was at; lovely UI but one CPU hogging little app. Sad to see these show-stoppers will now never be picked up in the future Sparrow. Who will be the new kid on the block?