Perhaps not as decisive and nose-turning as the pronunciation of Bianchi (Bee AHN kee, or Bee-AHN-chee). The pronunciation of panniers does lead to some minor campsite squabbles and uncomfortable blank looks at bike shops when members of separate pronunciation camps try to communicate.
19% (21 votes) pronounce it the French way...Pan-NEE-yay
54% (59 votes) pronounce it the 'Merican way..Pan-yers
26% (29 votes) pronounce it some way that is not rooted in any known linguistic logic (just kidding) PA-neers
Sadly, when I walk in to most bike shops around my area, it doesn't matter how I pronounce it since they don't know/carry panniers.
From Sheldon Brown:
Contrary to popular belief, "pannier" is not a French word, and should not be pronounced as one. The normal English pronunciation is: "PAN-yer".
"Pannier" is, in fact derived from a French word: "panier", a basket (more specifically, a bread basket, from "pain", the French word for "bread."
If you want to HEAR it spoken, click on the little speaker icon on this link from dictionary.com.
In other news...check out the new poll. What kind of pedals do you use?