I bought this as a joint present for my 2 1/2 (girl) and nearly 4 year old (boy) for Xmas at half price (which I think is about the right price in terms of VFM). My 4 year old is already quite accomplished on the Wii and DS and has not been all that taken with it, I had hoped it would be more engaging for him to make him jump around a bit rather than just sitting in front of the Wii/DS. But my 2 1/2 year old, whilst needing a bit of help to understand what to do, has really enjoyed it. I would recommend it for a younger child of 2-3 or an older child that is not already into playing on consoles as it's an easy way in and is good to have them up and about. Seems quite durable and is preloaded with 8 games, although as another reviewer has said, a number of them are quite similar concepts, having to move up and down to collect honey pots, musical instruments etc. For a younger child again, I think this repetition is educational but my older children just found it got boring quite quickly.
A positive is that there are 3 profiles on the system, so each child can build their own profile, earning their own points etc. The negative of this is that you have to reset the system in order to change profile, so it isn't a case of simply each having one turn.