iPhone sync takes ages

I vaguely remember reading something about this before (and how the 2.1 firmware was supposed to make things quicker), but I've just connected my iPhone to my Mac and it's taken around 20 minutes to sync. I needed to make a call during this time but obviously couldn't without breaking the sync process.

Considering the iPhone's connected via USB 2.0, surely it shouldn't take this amount of time just to copy data to/from the device?