Ombre Revisited

Ombre is everywhere on celebs (or it seems that way to me) probably because I love it and wish I could pull it off.  My friend, Allison just took the Ombre plunge and it looks amazing!  I originally posted about this hair trend over a year ago so clearly it's here to stay.  My fave celeb who wears this trend is Lily Aldridge (top three images).  I think her color is perfect!  I don't like the Drew Barrymore version with super dark roots and blond tips.  I prefer a more subtle ombre. 
I will definitely be asking Allison (my hairstylist) at White Salon, can I pull this off?  I'm thinking my hair needs to be a bit longer...