First, lots of the new MacBooks and MacBook Pros won't run PocketMac. It's a known issue and there is no fix, other than to throw it away and buy
Mark/Space's Missing Sync. It's not free like PocketMac, but it solves the problems a lot of new Mac users are having. And it's a really good program.
While you technically don't
need a memory card, I consider them
critical to a Blackberry. The Bold has almost enough internal storage to use without a memory card, but you're still WAY better off with one.
If you're looking to transfer files to your Blackberry from your Mac, the best way is by using the USB/Mini-USB cable and connecting the two through that. The BB should ask you if you want to go into "Mass Storage Mode" when it's connected, which you do. Then the memory card should mound to your desktop like any removable media. Then you drag and drop files into the sub-folders of your choice.
You can also pair your BB to your Mac via bluetooth and use the Mac's built-in bluetooth file exchange to send stuff to the BB. The downside to this is that for each group of files you want to send from your Mac, you first have to go to the BB, open the Media application, go to the type of media you want to import, and use the menu key to select "Receive Using Bluetooth". You can select multiple files on your Mac to send all at once, but you have to manually accept each one on the BB as they transfer over. And bluetooth is slower than USB.