1. I am having the same problem.
2. I had the MacBook Air which I upgraded from 10.7.3 to 10.7.4.
The sync process with my Blackberry Pearl 2 would take forever, but it would successfully sync.
3. On another MacBook Air with a Blackberry Bold, when the upgrade was made from 10.7.3 to 10.7.4, the sync wouldn't work.
I called both Rim and Apple, and it turns out it's a problem with Apple.
When I downgraded to 10.7.3, the sync worked again.
4. Now my problem is that I just bought a new MacBook Air that comes with 10.7.4 and I'm using it with my Blackberry Pearl 2.
The sync doesn't work.
On my MacBook Air, I only have "home" that contains all my appointments in my calendar which I exported to my desktop, then I deleted the "home" calendar (then I recreated a new calendar also calling it "home") hence making the calendar completely clear.
I also cleared all calendar items off my Blackberry Pearl 2.
I opened up Blackberry Desktop Manager and it shows "Home" "Work" and "Reminder".
Firstly I don't have "Reminder" anywhere within calendar.
Secondly, when I made the sync supposedly from a clear calendar on my MacBook to a clear calendar on my Blackberry Pearl, I should be syncing nothing to nothing from nothing.
BUT appointments were transferred to my blackberry AND my MacBook calendar is still clear.
5. Apple, please fix this.