Those of us devoted to our haircolor routine fall into two camps: those of us who do it for fun, and those of us who do it for necessity (or what we think of as necessity!).
Those in the "fun" camp enjoy changing up their color every few months or so and relish the freedom that comes with getting to be a redhead one day and a blond the next. The "necessity" camp either started going gray pretty young (I started getting enough gray to be really noticeable at around 30) or for whatever other reason (maybe your blond hair is your signature but your natural tone has darkened) feel the need to maintain something different than what Mother Nature endowed you with.
No matter what camp you fall into, staying up-to-date on trends makes sure your dye job never gets dated. Trends for fall include:
Bright or pastel offbeat colors: Pink streaks seem to be big with my mom friends these days, and I've seen green and blue as well. It's daring and maybe something you shouldn't try if you work in a more conservative field, but can be super fun if you have a little more freedom.
Ombre color: A darker color close to the head descending into lighter color and highlights. Done right, this looks like summer beachy blond grown out naturally (think the way yours might have changed when you were a kid), done wrong it looks like you are just not maintaining your color properly.
Warm blondish brown: This happens to be the hair color of both my children, so I love it. This works with a lot of skin tones and you can do a lot with it: add red or golden highlights, dark brown lowlights, or leave it as it is.
Of course, the best color is the one that looks good on you. What haircolor trend are you trying this fall?