To add to WestsideWeddings growing list of iPhone apps... Here's a list of some pretty interesting iPhone wedding applications I've come across recently:
iWedding - wedding event planner (comes with counter, budgets, lots of lists).
iBridalGown - need to find a wedding dress? There's an app for that! (Sorry that line is pretty catchy.)
Wedding List - Wedding guest list app by the folks from iWedding.
Wedding Day - Countdown app till the big event (I know I have one on my iGoogle!)
Personally, I'd like to take over the whiteboard at Westside Wedding's place and start making some flowcharts!