Agree with the PP that a meet the baby should be for actually meeting the baby. I had one for our son even though people live locally...I just had it 2 weeks after he was born, had told our relatives way in advance that we were going to do this. So, while our parents and siblings came up to the hospital to visit, extended family and friends didn't. So that's when my aunts and uncles and cousins and friends actually really, truly met the baby.
We did invites mostly via facebook and email since the date was unknown until I actually gave birth. My sister hosted it at her house. We did a baseball theme and served hot dogs, nachos, sugar cookies made to look like baseballs. We did do a printed invite for grandparents since they appreciate that kind of thing. But everyone else got a facebook or email invite.
Tis okay if your family is squeamish about breastfeeding. These aren't long parties - 2-3 hours is plenty and you wouldn't breastfeed in front of them. Just excuse yourself to another room for a bit.
Our invitations called it a "Meet the Baby Open House" so that people knew that they could come and go at any time between 11:00 and 2:00. We did put - "please no gifts; really this is just a date and time to come meet the little one"...meet the baby parties aren't common amongst our friends, so I wanted to set the expectation that we really didn't need or expect anything.
I'll definitely do one again - I thought it was perfect!