Not got a baby yet but MIL made it clear, on the same day that we announced our pregnancy to them, that she wouldn't be babysitting. Not that we expected her to, not that we were going to ask her, and in fact it would be a pain in the bum and more hassle than it would be worth to coordinate due to distance/logistics (we don't drive), but there you have it.
My mum has offered to look after baby on Fridays. Again, this will be more hassle than it is worth, financially speaking, but it is clear that spending time with the baby is important to her and I am willing to have the inconvenience to enable them to spend time together. And she is planning to retire early to spend more time with the baby and any future grandchildren. I imagine this will probably include some weekends and school holidays. We were often sent to my grandparents during school holidays when younger and both my parents are already desperate to have baby to stay with them. Of course that would be on their terms as far as possible (am sure they would take baby in an emergency) and we'd happily use paid childcare otherwise. We may well also ask my cousins to babysit on weekends, when the baby is a bit older, and we'd pay them for that.
We already do mainly 'family' things on weekends, we see both the in-laws and my parents/grandparents almost every weekend and wouldn't want that to change. My grandparents have expressed willingness to babysit on weekends etc but they are in their 70s so I wouldn't want to impose too much on them as they already do so much for us (cooking dinners and just general emotional support etc). Maybe in a pinch I would.
Finally Mrs J on 18th June 2011 ~ * ~ A born 11/01/2013