I did something similar a little bit more directly in my finance visualization app. (It's written in F# and there was a .NET Treemap control I could easily use.

I did something similar a little bit more directly in my finance visualization app. (It's written in F# and there was a .NET Treemap control I could easily use. At the moment it mostly relies on Mint [Intuit] CSV exports, but the benefit to that is that I could treemap based on the Mint categorization tree.)