Preparing a Child for Piano

I could probably write a hundred pages on this topic:)...... but at my sister's recent request I'll just start with a few pointers. The task of playing the piano involves so many different elements it may seem a daunting task to know where to begin when teaching a young child. Yet there are so many things that a parent can do to prepare their child for success at the piano before beginning to pay for formal lessons.
I enjoyed Natalie Wickham's recent interview about fun music activities for children on Music Matters Blog on this subject. She includes some great ideas for instilling rhythm, music appreciation and understanding basic piano topography.
During the first few sessions of piano preschool I did several activities that could easily be done at home to help parents introduce their little ones to the piano. Following are just a few... but if you go to the oldest posts on my blog and read "backwards" you can find more ideas in the general order that I introduce them.

Feel the beat: Steady Beat Elephants or Head Shoulder's Knees & Toes (you can listen to and print this song here if you aren't familiar with it).
Right & Left Hands & High and Low on Piano: "Piano Pokey"
Finger #s : "Where is One"
Find and play the groups of 2 & 3 black keys on the piano.

If you have some basic piano training yourself including knowledge of proper piano technique, it might be fun to "jumpstart" your child's learning by actually purchasing a beginning method book and teaching your child their first piano lessons.
My FAVORITE piano book for young beginners is "My First Piano Adventures" by Nancy & Randall Faber. It costs about $10 and has a fun CD to go with it. It introduces the concepts very slowly for young beginners. I think I would pay $10 just for the CD because I like it so much :) There are also some really cute "pre-reading" songs you can print off from Susan Paradis's site that my children have enjoyed to help them to learn finger #s, left & right hand.
Try... What the Robin Said to the Worm, It's October & Wiggly Worm -
For the first week I also encourage them to "play around" on the black keys with fingers 2&3 or 23&4 and make up their songs for fun.