As a teacher, and not yet a parent, I have a different opinion on the whole report card things. As Sarem mentioned, with the proposed A-E system, a child who is achieiving at their year level, will get a C, ahild who is 6mths ahead a B, and a child 6 mths behind a D, and so on. My problem with this as a middle school teacher (a year8/9 class) is that I have a huge and i mean huge range of abilities - i have studnets who are achieving a good four years behind what they should be due to literacy and learning difficulties. Now, these students still put huge amounts of efforts into their work, yet if they were to get a grade reflecting how they stood in the year level, it would be an E or F or U. Not much for the whole encouragement! Yes, I think it is important to get relevant comments from the teacher, that shows what they have achieved, but also points out future areas for improvement. I personally think that these comments are more important than a grade. However, the comments are limited to space, so if you've got queries or concern, I know I would be happy to talk to a parent at any time, and not necessailry leaving it to the end of term and parent evening. How relevant is it to know how your child is doing, compared to other students? I don't think this would really affect your child's own learning and its much more important to know what your own child is doing and what things can be worked on in the future. I really don't think this is important in early years of schooling, maybe later on and definately in the senior years.
Not sure how the A-E system will reflect progress from year to year, they will just either get a C each year if they are achieving each outcome to that year's standarr or grades either way. A better way to see improvement is with student portfolio's that they build up every year - you can see how their writing has developed each year and if it has changed in sophistication, etc.
I think there are better ways, and I think one of them, is ongoing communication with parents, initiated by both the teachers and the parents.