Sync your contacts in iTunes using google contacts, that's how I moved from a iPhone 4 to Android about 1.5 years ago and how I will move back to a iPhone 4 in a few days.
I have all my contacts centralized with Google, since both Android and the iPhone have access to it I can share it across my Xoom tablet and soon to be iPhone 4 once I get it.
Use My Contacts Backup from App Store to export your contacts to your e-mail as CSV(Excel) and then import them to your gmail account synced with your android phone. No hacking involved!