What I should have said was to the effect of syncing cloud based calendars, i.e., gmail, alongside Exchange. If you chose to sync Exchange calendar events, you are then forced to sync over the hardline for iCal, etc. Or, you can push exchange through iCal, blah blah blah. This causes duplicate entries in iCal and the need to sync over USB in order to be updated. Same holds true for Contacts.
My Palm Pre accepts credentials for both accounts, merges each systems' calendar and contact entries into the view, all over the air. I refuse to post personal calendar entries into my Exchange system, and vice versa.