When I sync my iphone to itunes, it takes forever and most of that time it says "Backing up Iphone". I just found a great tip on line that says the reason the backup takes so long is not the backup itself but the time it takes for errors and bugs to be reported to Apple. On that first day when you sync the iphone it prompted you whether or not you wanted error messages sent to apple. You probably said Yes like i did, thinking it was new and if you had a bug, you would want Apple's help.
To remove this setting, all you have to do is right click on your iphone in Itunes under Devices and click Reset Warnings. Now disconnect and reconnect and you should be prompted to report errors or not. NOT! Now sync and see what happens.