Mostly this babe's movements have stayed the same--which means moving A LOT. In fact, DH got a video on Easter night (so about four days over) of the babe looking like it was trying to crawl out of my stomach. It was pretty sensational!
I've only had two days where the baby has been really quiet. The first day I actually called my MW in tears and she sent me for an NST at the hospital. Of course once they put the cold gel on my tummy, the baby started riverdancing.

The other was just a couple days ago, and DH talked to the baby, and it moved, but not large movements like usual. I just kept track of the little movements, and as long as they were still happening I was okay.
After going through the NST (which was actually pre-EDD), I would say if you are in doubt, go have it done. It was totally non-invasive, and completely reassured me. I would expect the flamboyance of the movements (sorry, couldn't think of any other word, LOL) to decrease, but not the amount, KWIM?
Anyway, that's just my opinion.

This is the first time I've gone over, and I'm keeping pretty close tabs on this little one--but I definitely don't want to shove him out before he's ready!