There’s been a change in method for entering a keyword hierarchy in Lightroom 5.
The > now indicates a parent to child relationship, the exact opposite of older versions. It makes sense in that the parent is greater than the child.
Here’s a random example where we start at the top and work our way down, unlike previous versions where we start at the bottom of the hierarchy.
After entering, only Button Upholstery will appear (unless you switch to the Keywords & Containing Keywords option).
This is how the keyword hierarchy looks in the Keyword List.
The pipe symbol | acts in exactly the same way. Lightroom Engineer, Ben Zibble says ‘Note you can still enter hierarchy in bottom-up order if you like, just reverse the sign: “High Back < Chairs < Furniture"'.