I think also "ready to go" is also accepted here (I have vague memories of seeing in in the FAR/AIM). It seems if you fly for Southwest you can just say "Ruddy"
. As said in the posts above the only time you say "Take-off" is when reading back your take-off clearance.
I always put on my best 'speedbird' accent and call "Ready for departure", which I also remember seeing in the FAR/AIM is accepted phraseology.
To be honest the R/T I've heard here is no more slack than in the UK. Perhaps as I'm in the northeast at a class C airfield there is a bit more professionalism, but even in Florida/Vegas I've never heard anything worse than in the UK. It may sound odd/slack to hear someone arranging a taxi by unicom, but that is what is what is designed for, in part.
Gareth.