YA! I had this same problem. I setup google sync to sync and was using gmail's app also for gmail email.. Then I setup it up under the BIS and synced the contacts and calendar that way. I thought it would merge or not copy but now I have like 3 calendar events and 10 contacts for each single one I had before...
Is there a consensus on which google method for syncing calendar or contacts is best??
I use google sync. I turned off the feature in email setup. Under my gmail account setup on my BB I don't not have that sync my calendar. Google sync allows me to sync all my families calendars and my contacts. I would duplicate contacts and calendar events when I my email settings syncing. Hope that make sense.
Posted from my CrackBerry at wapforums.crackberry.com
Doing it directly through google, not bis, should be the best option. Google is pretty good with the storage of their(your) data, and you should not have a problem.