Well there's one big difference for me... say out of 15 times, testing 4g, on my first evo (pre ordered hdw 003), the best I got with 4g, where I live, was 4.5 mbps.
But that was only 2 out of 15 times. All the others it was worse then 3g!
Just tested the new(er) evo, with the update, and just got 5.99 mbps! but only .8 up. I'm betting the update made that difference.
Not exactly empirical testing but... Really liking the replacement Evo, has the epson screen which does seem sharper. It's a great phone.