This song starts with Kjartan playing the 
intro on his guitar, which is:
        
     
|G-------0-------|------0-----------0-|-----0----|-----0------0-----|
|D-----0------0--|----0------0--------|---0---0--|---0------------0-|
|A-3s5--5--5-----|--5----7s9---9s10---|-7--7-----|-7--7--7s10---9---|
                                     
                                    *3
|E--17--15---17--14--:|--19-15--19-14-|-17--15---17--14--|


8/4 | em | D11 | 4 times

then:

8/4 | C1 | bm | C1 | bm | am | (4/4) G | C2 | D Dsus4 |
(4/4) em |(6/4) C1 | D | (4/4)=only for this bar)

Then the guitar "intro" returns, with a little guitar melody:

|:-19-15--19-14-:|--19--|

8/4 | em | D11 | 4 times

8/4 | C1 | bm | C1 | bm | am | (4/4) G | C2 | D Dsus4 |
| (4/4) em |(6/4) C1 |
    | D | 4/4 C1 | C1 bm | em |

Here starts the second part of the song. Before the real climax, this part
is only played over | em |
When the band enters they play over | em | D | C | 
There's a part in there where it's just drums and guitar
|E--0--2--3--5--8--|
In this part Jónsi is actually playing with his fingers.  

fingerpicked..
|--17trem--20trem--19trem--|

somewhere in there you can hear unison bends:
|e--12----| 
|B--15b17-|

some chords:
    
    D11  C1 C2 Dsus4
|e---0---0---3----3---|
|B---3---1---3----3---|
|G---0---0---0----2---|
|D---4---2---2----0---|
|A---5---3---3----¤---|
|E---¤---¤---¤----¤---|