Played her a while back when she was considered OP. Honestly, she was. It was pretty much you have a Sona, or you'll lose.
But then after the nerfs, I found she got a hit just a little too hard. Not a horrible champ, but definitely got knocked from her spot as the best supporter. Her mana costs were brutal, damage lowered, cooldowns longer, movespeed buff nerfed, and they also dropped Innervating Locket, which was a huge indirect nerf to her as well.
After all was said and done, I'd rather pick Soraka than Sona...
But now I'm really considering taking her up again as my main (I main support champs.)
Thoughts on the new improved Sona?