I really hate the term "microgravity." It is supposed to convey that people in orbit around the Earth are only subject to a small, immeasurable amount of gravity, but that simply isn't the case. They're actually subject to a
rather large amount, it's just that their "ground" is also subject to it and is falling just as fast as they are. There are subtly immeasurable variations in the local gravity field due to the spaceship itself, but there is nothing "micro" about the total gravitational force, aside from how it would be measured without a known external reference (like the big honking planet right outside the window, which I think qualifies).
Personally, I prefer the term "freefall," since it explains exactly what's going on and follows every implication perfectly (relativistic effects included). What do other people think?