Definitive land pattern for 0603 SMD capacitors?
It depends very much on how the boards will be assembled and soldered.  If you are doing it manually then it will not matter too much.  I try to pick a slightly larger footprint for my DIY boards because that makes it easier.

If the boards will be professionally assembled then the footprint will definitely matter.  There are often slightly different requirements for e.g. reflow soldering vs. wave soldering.  This is when you'll need to work closely with the assembly house to work out what size and tolerances they can work with.