I've also had far better success with Missing Sync over PocketMac on Leopard 10.5.2. PocketMac can support more applications (Now Up To Date, Entourage), but if it doesn't work, then there's some unhappiness that comes from that. 
Missing Sync does a stellar job with Address Book, iTunes (with a media card), iPhoto (for grabbing pictures taken from the phone) and iCal. There's still weirdness with it, 'though -- or maybe with the Blackberry Pearl itself. Sometimes, I get reports that there is no media card (I have a 2 Gb micro SD installed on my 8120). Sure enough, the BB doesn't see it's own card. Go to play music or audio books, and no media (but I can format the card if I want). Pull the battery, count to 20, put it back in, and once the device reboots, the card is there to use and sync.
So there's some strangeness to the 8120, and to the sync. Doesn't help that Apple kind of seems slow in fixing 10.5 issues -- so very much changed under the hood from 10.4. And I suspect their roadmap to 10.6 when they finally abandon PPC support will see yet more changes. Man, and I thought the jump from 10.2 to 10.3 and the memory spec changes was painful
Still -- the BB experience from a user perspective is not what I had hoped. Really thought it would blow away my Nokia phone -- but doesn't. The wifi is nice but eats serious battery even when not surfing... so it stays off unless I have to use it. Bluetooth stays off period until RIM changes their OS for compatibility.
It really takes a lot of playing to get things functional. Keep trying, and report what works for you, so the rest of us Mac users don't lose hope and starting thinking of eBay when the 3g iPhones come out
(RIM: before you blackball me from the forum, do know that I'll tolerate a lot rather than go back to AT&T -- but you guys really could do to take advantage of the features in 10.5 and Mac hardware like bluetooth syncing.)
