TreeMap provides an easy, yet extremely powerful means of creating beautiful treemaps for analytical and presentation purpose. Importing data from a wide variety of file formats (including of course Excel), as well as connecting to databases (such as MySQL and SQL Server) is a breeze... and it scales to big data.
Via Robin Good, Jimun Gimm
This is another post where I recommend that you scroll down to have a look at Robin Good's great commentary. I can not beat his for details. His Scoop.it site is: http://curation.masternewmedia.org/ Thanks Robin!
If you are looking for additional visualization tools for displaying data, TreeMap v. 3.0 offers a classic tree map layout as well as others, like squarified variant, circular, tag cloud and voronoi.
Interesting tool, give it a try