When it gives the ability to make Omods and Fmods then I'll be happy. For now it's a bit basic, but it gets the job done. The ArchiveInvalidation feature is especially nice and if you use texture mods at all, you needs to have that installed or you will get black texture bugs.
I use 7z to create fomods, because that's all fomods are really.
If I download a mod that isn't set up as a fomod, I just extract it to a folder, then 7z everything up inside the folder and give the 7z the name of the mod, so I end up with something like
"Glowing Ore Veins 300.7z"
inside the directory structure is something like:
\Textures
\Meshes
(So that if it was extracted manually in the data folder, everything would go in its proper place)
Then I just use NMM and pick "Add Mod from File" and browse to the 7z I made, and install it as a Mod Package.