Logo or Python (Score 1)

Either logo or Python would be good choices. Logo has been around for years, and there are lots of good books and free implementations. Start at Brian Harvey's web page for more info. Logo is great because of its pretty simple syntax and turtle graphics, which lets you start drawing pictures right away.

Python is showing lots of promise as well -- its interactive, fairly simple syntax, has turtle graphics, but not the wealth of books for the younger set (actually, none). However, you must check out Alice - interactive 3D graphics for the web, with scripting for animations done in Python. Thats what I'm starting my 10 year old daughter on, falling back to logo if that doesn't work out.