Finally, and I have no idea why it has taken so long, Nokia has released the Nokia 5800 XpressMusic iSync plug in, which will no doubt have Mac owners jumping with joy.
iSync is the Mac equivalent of ActiveSync so finally Mac owners can now sync their Nokia 5800 XpressMusic contacts and calendars with their computer.
iSync for the Nokia 5800 XpressMusic can talk the hassle out of managing data transfer across devices and can be downloaded from the iSync page of the Nokia website and once installed it should be fairly obvious what to do next.
Source — symbian-freak