Thank you for posting this information - I just got myself a 4tb drive (actually its only 3.6 tb) and it works GREAT as fat32 - or as NTFS logical. I was going to add this to the wiki but could not figure out how to do it properly - I made a post with the following info on it... I'm pasting it...
I hope this belongs here:
Good news - Now there is a 4tb hard drive that works on the Wii.
Bad news - I can not put it where it belongs, I would have to drop it down into 'other' because the highest available section is 2tb. If it is possible for a user like myself to add a new 4tb section...