I guess I didn't address this before, but have received some e-mail about it, so here are my thoughts on synchronizing your Blackberry and your Mac:
There are currently 2 sync solutions available to synchronize your Blackberry and Mac: PocketMac and The Missing Sync. Although I have use The Missing Sync for Windows Mobile, I have not yet tried the Blackberry version for this simple reason: PocketMac is free. That's right, RIM licensed PocketMac as their official Blackberry OSX software, so you can get it free of charge. I've been using PocketMac since I got my Pearl and it work great -- the interface looks just like iSync and synchronizing couldn't be easier. The Pearl actually detects when it is connected via USB and allows me to choose if I want to enable mass storage mode for the memory card, which allows me to easily add/remove ringtones, wallpaper, pictures, etc.
The Missing Sync seems to perform many of the same functions as PocketMac and I would highly recommend it if you are a basic or non-advanced user as the interface is very polished and interaction with everything on the device happens via its application. Bear in mind, however, that you pay $40 for that convenience.
My vote's for PocketMac, so that's the link you'll find again below (note that the download link will take you to RIM's site where you'll have to give them some personal info in order to download the software).