I'm not going to tread through 11 pages of wannabe internet legal experts analyses to check if there's a modder's point of view in there, so here's one.
Fact : Modders work first of all to improve a game they love and share that improvement with others. Not for money or fame, just to contribute to the modding scene, for fun, and maybe learn a bit of modelling/coding on the way.
Fact : unless you've been pretty deep into Morrowind mods for a while, it takes hours, nay, days to find, download, install (compatibility issues anyone?) such a set of mods. Mod compendiums make it possible for lazy people to enjoy those improvements. So why wouldn't modders be happy with that ? Here's where fame comes in - sometimes mods are recognized enough that their creators actually get job offers from videogame producing companies (among others, Ossian Studios recruited Neverwinter Nights modders). Either that or, you know, that infamous INTERNET REPUTATION thing. What are you all trying to do here anyway, writing thousands of posts ? Trying to make an internet name for yourself ? Most of you would make gleeful noises inside if someone mentions your nickname somewhere... ah, sorry, enough psychobabble. Thing is, by making that mod compendium, that guy there would be getting all the fame some of those modders think (not without reason) they deserve.
What if he'd asked for permission ? Sure, most of the modders would've agreed. (there ARE a lot of authorized mod compendiums out there, a few of them quite large too - mostly graphic improvements or item mods) But those who sent him letters threatening with legal action - those wouldn't have agreed. Those guys want people go to one of their mod release pages, look at their name, read the description they wrote, and download their mod. Not judging, mind, that's just the way it is.
Also - some, let's say, uneducated people here were stating mods are not art. Right. Because designing, creating new or improving old 3d models, painting textures, writing dialogues and scenari - not art. Nope. So you're one of those real grown-ups eh ? Feeling a bit alone now that Mr Ebert wisened up ?