Actually I'd argue that Nanoha as a character really didn't do anything that awesome until StrikerS and the final scenes there of. As a whole she felt kinda generic. The only thing really different about her compared to other magical girls is she has a bigger, metaphorical, 'gun'. I'm okay with it being top of the list though.
Cardcaptor...eh. It's okay in second.
Madoka...ugh. Still don't get why people like this show. ~.~ It's pretty much ruined by one freaking huge plot hole that turns the main character into an unlikeable douchebag.
Oh hey, my friend and mentor died and I'm not even going to [b]try or ask[/b] about
using my 'wish' to bring her back to life. And never mind any thoughts that she can't, because at
show's end it's revealed her wishing power is enough to [i]reboot the entire damn universe.[/i]
Huh, guess you didn't really give two craps about Mami and pretty much just faked your sadness
about that incident the entire show.
Sailor Moon should've been taken down a peg or two. It was good for it's time and did help evolve the genre but that show really isn't aging well.
Kamikaze Kaito Jeanne deserves to be a few spots higher. Maybe even more so than Sailor Moon as I felt it had stronger characters and a far better lead.
I don't think I've seen anything else on that list. But I am rather astounded that Mai Hime and Tokyo Mew Mew didn't even grace the lower ends of it. So much so I'm almost tempted to call 'foul' on the list as a whole. They're both at least B - B+ grade Magical Girl shows in my opinion.