We are also travelling for Vanuatu - but for a wedding in July - it has been difficult to turn up a great deal of information - there is a small amount on this Forum - just put Vanuatu in the Search function at the top of the page.
If you do a Google search you will also find some more - as well as Trip Advisor.
We are staying at Le Lagon, where the wedding will take place and there are about 40 of us travelling from Australia so if should be lots of fun.
I have the impression that it is very laid back and accommodation is adequate but not over the top - rather 'tired' is the impression I keep getting.
I hope that we can gather some more help through this post.

We have just returned from our 5 day trip to Vanuautu and enjoyed it immensely.
We were part of a wedding party of 56 adults and 19 children but Le Lagon Resort was perfect for the purpose and being a large resort coped well with not only our group but the hundreds of others there as it was school holidays.
We had a room on the first floor looking over the lagoon, it was quite small but comfortable, but rather tired looking. However the bathroom was large.
The resort itself it very nice and because it is very spread out can cope with the large crowds of people.
The meals in the main restuarant were fairly hectic but the staff coped well and I am sure it would be much better out of the holiday period.
There is also a Bar & Restaurant by the Pool and another more upmarket one which serves dinners only.
The children had a great time and happily took part in the Kids Club some days.
It was an easy bus or taxi trip downtown, where of course there was a variety of restaurants, a huge market place and interesting places to see and things to do.
The bridal couple were very impressed with the efficiency of the Wedding Planner, and the ceremony itself and reception afterwards (all held on the beach) went off without a hitch.
The weather was lovely - hot during the day and cool in the evening and overall we could not fault our holiday..