Just my two cents:
Even with all actual limitations, the 2009 software version worth every penny you spent to get it, if you do not rely on old important 2007 files.
For around $30, you will get new street data, new 3d navigation mode (this one is a must try, this is the only full screen navigation mode i am using now since i switched from the 2007 version and i will never come back to the old 2d "sky" mode (but only in very few occasions), as it shows least info on the screen), a much better available S&T Keys 2009 free addon, speaks street name, easier move/zoom mode (no button to push), location coordinate displayed bottom right of screen, a little faster, compass available in full screen navigation, gps trail crash bug corrected, and so on.
The only feature i can say i missed a lot from the 2007 version is the 2 arrows to undo/redo actual map operation. But this won't make me return to old 2007 for no reasons...