My little girl is 13 months old and received this shape sorter as a Christmas present this year. She must have known she was going to love it because she was screaming with excitement before the wrapping was even off! As soon as she got her hands on it she knew what to do. She knew the pieces went in the little holes and she could reach in and get them back out. We had to hide it in order for her to pay attention and open her other gifts!
This shape sorter is great because it's not the typical block sorter. This has 6 different shapes to drop in the corresponding shape holes. The sorter is in a cylinder shape so it can be rolled around with the pieces in it and it makes noise to entice babies to chase after it. On one end there is a plastic mirror and on the other end there are four, thin plush pieces of fabric that hold the shapes in. You can reach in this end and take the pieces in and out.
The packaging recommends this for babies ages 6 months and up, but I would say 12 months would be more appropriate. The shapes are a little small and I'm not sure a 6 month would understand what to do. My 13 month can get the pieces mostly totally in her mouth, but they're too big to swallow. The danger is just that she will get it stuck in her mouth, so I keep a close eye on her when she's playing with it.
She loves this toy so much I think because it is so colorful. She can't do it by herself yet, so when she wants to play with it she either brings me the whole thing or takes a piece out and hands it to me. She loves to look at herself and kiss the mirror too!