Okay first a small praise is in order.
First of I wanna thank Bethesda for the amazing 30+hours experience I have thus far, the awesomeness this game offers you can not be described in mere words...

I've got 250+ hours in Oblivion without useing a single mod.
Now I haven't been using mods so far because I simply felt that the use of these so called mods might be to much to handle for me.
Is it hard really to imply those mods in your game, or is it simply downloading files and dragging them in a folder?
I've been asking myself this because I am already dreading the day that Ive completed all main questlines in Skyrim and the game becomes ''dull'' for me.
If that's even possible lol

So my question is, what are your experience(s) with mods?
Do they really contribute to the amount of gameplay that you get and are they really worth it?
And is it hard or rather easy to install them?

Coming from a noob obviously...

Thanks!

Don't worry about the installation process, it's extremely simple to do it manually (just drag'n drop some files into the "Data" folder inside your Skyrim folder) and it's even simpler to use the mod managers I'm sure someone will create in the future. There is a Nexus mod manager in development, which gives you access to the largest TES mod website and it automatically installs the mods for you.

Mods are fabulous. I love the options to tweak the game.

I've used mods since I played Morrowind. I think I completed the game once and then my brother told me that we could change things in the game with the Construction Set. It opened up a whole new side of the game. I started by just changing around stats on armor and weapons. That evolved to adding new spells and other things. Eventually I found some really awesome websites that had TONS of player made mods. I started downloading them and never looked back.

I will say that you should do some research first about how to install them. There is info about modding on UESP.net as well as many other places. A big name in modding websites is the Nexus family of websites. Check out Skyrim Nexus. It only has a few mods now but more will be coming soon.

The Creation Kit should be released soon (I hope!) and then the fun will really begin.