In the lead up (say, in the last couple of years of my 20's) I was really dreading it. I have always looked younger than my age and never used to tell people how old I was. But once I hit 30, I made a conscious decision to embrace it and have since been forthcoming with my age. Don't really know why... maybe because my children are getting older and its really hard to pretend that you are 20-something when you have two teenage daughters that are taller than you!
I am now 34 (35 in a few months) and I feel really comfortable with my ageing, even with the few silver hairs that I've got. I feel like they are testament to the interesting and challenging life that I've lead thus far.