I would say going from 2 to 3 is definitely a lot easier, although that depends on the baby.
Mine are girl of 9, boy of 4 (5 in 2 weeks time) and baby girl of 3 months.
Because I am one of only two (older brother), I always wanted 3. Even when my son was born, even though I had one of each sex, I still wanted another.
I found the pressure was off when I was having a third child, as no-one presumed I was going for one of a particular sex as I had one of each already. If I had had two girls, or two boys, I would still have gone for a third as it was the child I wanted, not the particular sex (if you know what I mean).
When I was pregnant, everyone it seemed took great joy in telling me how hard it would be. Well, as a mum-of-3 now, I can not emphasise enough how easy it is.
My daughter is an absolute godsend (she can't do enough for her baby sister) and my son likes to feel important as he has to choose which babygro she is going to wear each night.
My baby is so content and happy - the most content out of her brother and sister.
I tell my children this :-
My daughter will always be special as she was my first-born.
My son will always be special as he is the only boy in the family (apart from his dad).
My baby will be special because she will always be the baby of the family.
If you want another, please don't be put off by other people's comments. For me it was a lot easier than going from 1 to 2, but that might be because my daughter is 9 years older and is such a help.
My daughter absolutely dotes on her sister, but I tell my daughter that when the baby is 9, she will be 18 and she might not be so keen on her then!
It doesn't seem that long ago that my first born was a baby and I hardly believe, at times, she is 9. It frightens me (!) to think that when the baby will be 9 my eldest will be 18. That is scary!