Making tree-diagrams with pdf output without using graphviz

I usually like graphviz a lot for making graphs and trees and outputting them to pdf files. Right now I have a program that builds a tree with a large branching factor (up to 12, usually closer to 8 or 9). The problem is that graphviz cannot draw the tree more than two or three levels deep (and less if I use my fancy labels).

My train of thought is that this is a very simple graphic to generate. It's a very generic tree structure and no specialized placement algorithms are needed at all. I'm wondering if anybody knows of another software package that might get the job done. Here are the features I'm looking for:

Bare minimum:

Draws really wide trees with many vertices (perhaps a few million)
Outputs to pdf, postscript, svg, or some other common, portable graphics format

Good to have:

input format similar to graphviz
nodes that can be colored
html-style tables, similar to the awesome ones that graphviz has

Solution

Have you considered TikZ? http://www.texample.net/tikz/examples/tag/graphs/

I have not had to make graphs with millions of nodes, so I can't be sure this will work.