I love that video of Joker and Harley...his movements, his body language...are spot on!
I'll admit when I saw the official pic of Leto's Joker I didn't really care for it that much...but now after seeing more pics of him on set, in clothes, and seeing that video...I'm really loving everything.
I can see more of what they're going for with the character.
They are really playing up his 'bad boy' charm, and giving him a bit of sex appeal...which is understandable since they have to explain to a general audience (who might not be familiar with the whole Joker/Harley dynamic) how a woman, ANY woman (crazy or not) could fall in love with the Joker, and still want to be on his arm, even after he smacks her around.
Making him more clownish (traditional) I don't think would have worked that well in explaining the attraction, giving him that whole bad boy/rock star edge...yeah I can see it.
The tattoos are just a part of that.
And although it's not the Joker I was initially expecting, I'm willing to embrace a new interpretation and after seeing that leaked video I'm REALLY excited to see Leto's performance, I can't WAIT to hear his voice!

t:
If I can love Ledger's Joker (even though I still am not crazy about his look) because of his performance, then I sure as heck can overlook a few tattoos if Leto's performance is half as good as that leaked clip hinted at.