Hi and welcome to Everything Treo. Unfortunately, the 700w does not support the Mac out of the box. There are third party software vendors that are working on a solution. I've been able to get the 700w working with my PowerBook. However, I believe it requires Tiger along with Bluetooth capability. If your Mac has that, it's possible that it would work. The software is still in an alpha version, so you'll have to wait a bit longer until it becomes available. Here's the
Mark/Space WM 5 status page.
As a workaround, I've found that emailing vCards is an easy way to get contacts into your 700w. Just drag the contact from Address Book, attach it to your email and send to your Treo 700w. The 700w is pretty good about adding vCards.
-Chris