Don't know if people would like this, but how about an
option to highlight matching nodes as you type your
xpath expression. (after each valid xpath expression.
For example highlight matching nodes when the xpath is:
/item
/item[@TypeId=3]
/item[@TypeId=3]/subitem
but not when it is:
/it
/item[@Typ
/item[@TypeId=3]/subit
matias@mac.com