It's really fascinating to hear everyone's thoughts on motherhood and the shift in one's universe that ensues -- both from the perspective of first-timers and those who are already living it!
Okay, so the following starts a bit me-me-me, but moves on to general philosophising about parenting as social construct and lived reality. But this is not a class and you may totally skip this post and I will not be offended! 
So, all the various unknowns aside, I do fully anticipate that my research and my book-writing will maintain, and hopefully this will be associated with an academic job post-Feb. 2015 so that I am paid for my efforts and able more easily to be part of wider supportive and collaborative academic community.
DH (ex-academic) understands the issues and is 100% supportive. He is also cognisant of the fact that both of our lives as they are at present must, albeit to different extents (a point I'll return to below), adjust to embrace and make sufficient nurturing space for the new people in our lives. In this short term this involves, for me, 9 months mat. leave, during which I will be engaged on some activities which most people would perceive as 'work', and for DH, the idea of going down to a 4-day week so he can contribute more in terms of day-to-day, hands-on parenting, plus us paying for childcare during mat. leave, both of which will enable me to do my 'work' activities in a phased return to f-t work.
But this raises a question for me which it would be really helpful to get others' perspectives on, especially those who are already mothers and who also work. I'm really interested in the extent to which your partners' or husbands' professional lives may have shifted or be about to shift to facilitate co-caring for your growing families. The social tendency (although I know of many examples otherwise) still seems to be that it is the woman's professional life that becomes the more expendable factor. It's really interesting to hear that for some this is a welcome and positive shift, a change many actively choose, but is there something inherent in parenting roles that means it is the mother, rather than the father, who more usually makes this shift, whether out of choice of necessity (e.g. the shocking gender pay-gap which means women on average earn less than men)?
In my case it's been kind of assumed, by both of us, that I will take 9 months of maternity leave, when in reality I could share half of it with him. DH appreciates the impact that will have and has volunteered to take some steps to ameliorate that (going down to a four-day week; possibly also some more working from home if his company allow). I am not sure I know what my overall question is precisely, but it's to do with the gender factor in assumed or chosen parental roles. Perhaps it's a slightly existential thing about whether motherhood (whether as social construct or lived reality) is perceived to be fundamentally different (more essential, maybe, to child development?) than fatherhood? A lot of the books I'm dipping into at the moment lament the fact that our choices are dictated by binaries (SAHM or work+childcare; mother or father takes bulk of parental leave). I would like to achieve more of a gender balance than the either/or, although I think the real issue here is my own curiosity about why I'm not pushing for more of a 50:50 split.
Sorry this is such an essay, but it's actually just really helpful to vocalise these issues which are playing around in the corners of my mind.
Dame you're mother sounds great and am loving your can-do positivity today. Go you! 