I believe the chords are 100% accurate, this is exactly how Alex plays it here: 
http://www.youtube.com/watch?v=CrjvHx-sIb4

Make sure your guitar is tuned half-step down!
Chords:
G - 320033 
Dm - xx0231
C - x32010
Em - 022000
F - 133211
Em7 - 022033
Cadd9 - 023033
D - xx0232

Intro: G Dm C Em F C

Verse:
 
G
Lazy lover
       Dm
Find a place for me again
    C
You felt it once before
           Em
I know you did
              F   C   (transition from F to C is quite quick)
I could see it

G
Whiskey Princess
         Dm
Drink me under, pull me in
    C
You had me at come over boy
  Em
I need a friend
  F        C         D
I understand
 
Chorus:

         Em7         
Backseat serenade
      Cadd9
Dizzy hurricane
   G                         D
Oh god, I'm sick of sleeping alone
                    Em7
You're salty like a summer day
         Cadd9
Kiss the sweat away
        D
To your radio

         Em7
Backseat serenade
       Cadd9
Little hand grenade
   G                         D
Oh god, I'm sick of sleeping alone
                    Em7
You're salty like a summer day
         Cadd9
Kiss the pain away
        D
To your radio


Fill: Cadd9


Verse:

G
You take me over
            Dm
I throw you up against the wall
      C
We've seen it all before
               Em
But this one's different
     F         C (mute)
It's deliberate

G
You send me reeling
        Dm
Calling out to you for more
    C                             Em
The value of this moment lives in metaphor
      F             C        D
Yeah, through it all


Chorus:

         Em7         
Backseat serenade
      Cadd9
Dizzy hurricane
   G                         D
Oh god, I'm sick of sleeping alone
                    Em7
You're salty like a summer day
         Cadd9
Kiss the sweat away
        D
To your radio

         Em7
Backseat serenade
       Cadd9
Little hand grenade
   G                         D
Oh god, I'm sick of sleeping alone
                    Em7
You're salty like a summer day
         Cadd9
Kiss the pain away
        D
To your radio

Bridge:
Eb|-------------------------------------------|
Bb|---0---0-----------------------------------|
Gb|------------0---0---0---0---0---0----------|
Db|--5---5----7---7---9---9---4---4-----------|
Ab|-3---3----5---5---7---7---2---2------------|
Eb|-------------------------------------------|

Eb|-------------------------------------------|
Bb|---0---0-------------0---0-----------------|
Gb|------------0---0-----------0---0----------|
Db|--5---5----7---7---9---9---4---4-----------|
Ab|-3---3----5---5---7---7---2---2------------|
Eb|-------------------------------------------|

Eb|------------------------------------------------|
Bb|------------------------------------------------|
Gb|------------------------------------------------|
Db|-55555555-77777777-99999999-44444444-55555555-7-|
Ab|-33333333-55555555-77777777-22222222-33333333-5-|
Eb|------------------------------------------------|


Chorus:

         Em7         
Backseat serenade
      Cadd9
Dizzy hurricane
   G                         D
Oh god, I'm sick of sleeping alone
                    Em7
You're salty like a summer day
         Cadd9
Kiss the sweat away
        D
To your radio

         Em7
Backseat serenade
       Cadd9
Little hand grenade
   G                            D
Oh aren't you sick of sleeping alone
                    Em7
You're salty like a summer day
         Cadd9
Kiss the pain away
        D
To your radio

End: Em7 Cadd9 D