I've certainly been thinking a lot about that lately!
If you have too, but, like me, you're still scratching your head on the subject, skip over to YouLookFab for a to the point post on Dressing your age
Not only does Ms. Angie speak to the types of clothing that can work for different age ranges but she names names of famous femmes who embody the look.
Well worth the read! (Pay attention to the reader's comments and Angie's wise replies as well for more tips!)