Nice site. Still a bit to do but looks nice, easy enough to use etc. You asked for thoughts on pricing. Unless you can get write-ups in wedding magazines (in my experience they should give you a wedding magazine when you buy the engagement ring because that is the first thing the girl buys after the proposal!) then you are going to struggle to get people to part with money without some level of trial, but 7 days might be enough.
Then a charging structure based on a wedding might be best, $50 for a wedding (especially if you can demonstrate the ability to save time or money) would seem very reasonable. Personally too much more would seem a bit steep but I might just be tight. Monthly would obviously seem better as a revenue generator, but doesn't feel right to me - this is supposed to be a once off event - even if it is the third time!
Some thoughts on site:
1. On Signup "Who are you" default who you are should be Bride. You may also want to include Mother of Bride in the list.
2. Timezone - why?
3. When - using US Date. Huge market for this outside of US. Either work out dates from browswer or dd-MMM-yyyy. UK market you'd have to make some changes as they divide wedding into 3 parts (church/ceremony, food, dancing) but it would still be useful as is.
4. Expenses - no total
5. Expenses - possibly you want a flag for provisional and actual - catering supposed to be 50 a guest x 100. 90 guests confirm so actually only 4500 and probably confirmed a few weeks before date
6. Guests - nice flow,liked that you didn't have to enter too many details, because I wouldn't enter much. Maybe make it more obvious they only have to enter a name
Looks good, wish I could have set my wife up in this when we got married. Good luck.