Windowblinds.

I find WindowBlinds to be more time consuming since it's divided in two parts. 1) Creating the designs of each part and 2) setting the codes for positions, lengths, widths, etc.
Icons work the same, and like Weaksid said, you need to make a lot of them to cover all the programs.
Cursors are sets of a consistence number of images [not as many as an Icon Pack]
Wallpapers for the most part are much easier to make, and you have a greater number of people making wallpapers as oppose to the ones skinning.
This is why you will see more movement in certain libraries and not in others.




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My last WB took over 50 hours but even I dont think I have enough patience for an icon package.

Why do you see no movement in FX? Is there just nothing left to do with that effect, or is it really difficult?

Window Fx are fairly cpu intensive so I guess that makes them unpopular.I thought they were cool but thay bogged down my 1ghz system.WB dosnt.

Oh, the worse thing has to be icons. By far. Pixel by pixel drawing takes FOREVER. There are very very few good iconists.

Windows Media Player is different. It can be long but doesn't have to. One would consider it difficult because it requires coding and most artists aren't programmers.

WindowFX is just plain coding. They're not skins, but plugins and effects you add to WinFX. Very little graphics, a lot of coding. Since there are a lot more artists than coders around these woods, it's normal that uploads aren't too frequent.

WindowBlinds requires the most work of the things I've tried, theres a lot to skin. Litestep can be complicated but like Jafo said, its freeform so it is as easy or complicated as you want to make it.