Well it is a bit a very late reply, but just to make it compleet.
It works, and there isn't realy a syntax for it.
Just type a part of the registry location, or the name of the product.
Default IgnoreList.dat wrote.hta
.htc
default.hta
Boot
CachePath
I386
OldWinBootDir
//Misc items:
Incredimail
PainShopPro
Paint Shop
PSP8
You can add stuff to it yourself like this for example:
//Ignore every thing about nVidia.
nVidia
//Ignore the windows registry folder in the microsoft folder.
Microsoft\Windows
I Hope this will help.