First of all, this is a fantastic deal because not only does the tablet come with uDraw Disney Princess, but also uDraw Studio.
The pros: easy to set up and use right out of the box- simply plug your Wiimote into the tablet and you are good to go! It doesn't require batteries. I also love the "storybook" environment of the game (and love the fact that it reads the text out loud- it's encouraging my daughter to read along and for little ones, no adult "can you read this for me?" is necessary)
The only criticism I have is that the Princess game is a bit simple for kids who are familiar with other Wii games. My daughter is six and regularly plays Rio, Tangled, Wii Party, Wii sports, etc. and she blazed through all the levels of UDraw Disney Princess in pretty much one sitting. There's not much room for creative "free play"- instead it's a lot of painting by numbers (not actually painting, but dragging a paint bucket over a certain area of the screen and dropping it), filling in missing items, waving the "wand" over areas of the image to fill things in, etc. My daughter is really enjoying it, but I can tell that one's she's done with all the levels and earns all her gems (which will probably be this evening), she probably won't pick up the game again. It doesn't have much of a repeat play factor.
Overall, I'm very happy with this purchase. I'm excited to check out also titles in the uDraw series. I think for girls 3-5, this is a great game. For older girls, I think the Princess game may hold only limited interest, but it's a good way to get into the uDraw series of games- it provides a great introduction into using the tablet and the stylus.