It's easier for me to understand text than graphics. I'd rather read the data than see the graph.
Also, the old interface is faster. Not sure if the speed is from load times or from the fact that I'm more familiar with it and can navigate it without a learning curve.
The new interface is both too customizable, and not customizable enough - kind of like Microsoft Windows. You have to learn the language, and then you get frustrated at taking all that trouble only to find you can't control everything.
If all the reporting available in the new interface were available in the old, I'd be pretty happy.