The upload speed is typically about what I get on Tmo 3G although I'm usually running about 1.3-1.5Mbps for download speeds. I'm in Minneapolis area, the 3G coverage here is pretty darn good but the signal on my N1 is considerably weaker than the MT3G3 that I had before.
So I finally got my old 2.1 market to work (thanks Rusty!) and downloaded SpeedTest to find out if there really is an issue with 3G speeds on the FroYo nexus one.
With FroYo, my speeds were between .5-.6 Mbps download, and 1.2-1.5 Mbps upload.
When I rolled back to 2.1 I got between 2 Mbps and 3 Mbps download, 1.2-1.5 Mbps upload.
Yup, there is definitely a difference. That being said, take with a heaping pile of salt that I run AT&T, and the FroYo release is not meant for any AT&T N1 (or any of our N1's for that matter). When the real version comes out, I'm pretty sure it will be just fine (but I'll check again to make sure obviously).