I just did a google search and here is one of the threads I found online, after first hearing about this type of MAF swap through some Maxima channels.
http://npora.ipbhost.com/index.php?showtopic=12280
I got that exact part number (22680-2Y001) and went to my local Nissan dealer. It was something like $120ish.
This would be the top link you listed.
Like I said, my 2001 QX4 runs much better and I have had this on for a while. However, it has now started throwing codes. I don't know if I need to get my ECU reprogrammed or if something is running slightly different and I don't know what it is. I can't really tell that anything is actually wrong.
For the cost of the fix and less than 1/2 hour of my own labor, I am fine with that. I just wanted to make it clear that this may not be the absolute best solution.