You'll be more likely to get help if you ask up in the Now X Public Beta forums. This forum is intended for questions about the older Now Up-To-Date and Contact, so I'm not sure how many people familiar with Now X will see your question here.

When you repost, it might help if you can include more details, such as if you see anything in the Activity window when you attempt a sync, whether you've confirmed that the events and contacts have the Sync tag, and whether anything seemingly related appears in the Console logs.

Dave Sawyer
iMac 24 2.8GHz Mac OS X 10.6.2
PowerMac G5 2GHz DP Mac OS X 10.5.8
Windows XP, Vista and Windows 7