The main draw for the N73 is the camera. If you want to take decent stills (good-great pics when the lighting is right) and don't need Wi-Fi, get the N73. Also, if you change up the firmware you can get the new music player from the ME version.
If you're looking for a smaller form factor, don't need a 3.2MP camera and want Wi-Fi, get the E65. Personally, I think the E65 is the better looking phone. That said, I own an N73 for the camera and as my everyday toy. E62 is my "biniz phone".
Check out e-series.org for a great review on the E65. N73 reviews are abundant.