Syncing is something I'm kind of torn with on Android. The first sync, setting everything up and all that, is a pain in the ass on Android. You have to basically have to load all your Address Book and Calendar data to Gmail. It was easy enough for me on the mac, but I could see a lot of people having trouble setting this up, especially people who are used to just plugging the iPhone in and having it do all the work for you. Apple is clearly better here.
But, after that initial setup, I much prefer Android. Why? Because there is no syncing. Everything happens over the air. I add an event to my phone, and it shows up on iCal and Gmail without me having to do anything else. If I had an event in iCal, it shows up on my phone. It's like Mobile Me, except it's free and it works. So I really prefer Android here.
If Apple started including Mobile Me with the iPhone (and worked out some of the kinks), then I'd say Apple is the clear winner for syncing.