Moving into a new home has always brought on a dilemma for me-clean first (and thoroughly!) or move in and then clean as you go. Plus there's the joy of fixing minor problems (baseboards, drywall dings and such).
My take on this so far has been to do the cleaning and fixing FIRST. Once one is moved in (and tired, no doubt) it's hard to muster the enthusiasm to clean and fix all the little things and they then end up staying the same (if you're like me) for a year or two before one has the time and or energy to get back to doing it all.
If I do all that fixing and cleaning first-even before closing once financing is approved and if I can get owner permission-the move in is much smoother and easier. No having to fiddle around and mop in the midst of furniture moving, no finding the spackle to fill in nail holes in the walls while moving in book shelves. Usually the previous owner has fixed most of this stuff, but sometimes they are in just as big a hurry as I am and don't have the time or patience to do it all-because they are moving themselves. If you can get in early and find out what needs doing, like baseboard replacement, shoe mouldings, door stops, etc, you can have your supplies on hand for early replacement and complete it before you have to deal with all the other moving issues. This helps remove some stress from what is already a usually a pretty stressful situation.
If you can, try to plan an extra day into your moving time to care for these small things-it will end up making things easier and less stressful, plus once your stuff is moved in, it will look better and those little things won't be there to nag you.
Trust me, you'll be glad you did.