Joined: 6 Mar 2009 16:53 PST
We discovered late last week that a recent update at 37Signals was causing trouble for some users syncing their Highrise contacts.
The problem itself was resolved by an update to our service that was deployed last Friday.
However we're recommending that Highrise contact sync users check their devices to verify that the correct number of contacts are present.
If they aren't, a contact sync reset (click the 'manage' link on the device page on our control panel site and follow the instructions to reset sync) will restore them.