I might be the only one that didn’t know this about Android but I stumbled on this the other day and couldn’t find this in the guide or anywhere else for that matter. You can move an app icon between homescreens by dragging the icon to the edge of the screen and waiting for the homescreen to shift and then drop the icon on the new homescreen. I swear I tried this back when I had 2.0 on my Droid. I didn’t try it again until 2.2 but it definitely works now. It works on the default home app and LauncherPro.
Moving icons between homescreens