My bunny Turbo used to do a lot of binkies a little while after he was let out of his cage.  Since I've let him go free-range, I don't see many binkies any more, except when he anticipates treats.  That said, he seems a very content bunny - he lounges around with his legs stretched out and he licks me alot.  I'm interpreting this all as sustained happiness replacing former bursts of joy.  But I like the bursts of joy!  Also, I can't sit and watch him all day, he could be doing binkies when I'm not around.  

Any thoughts?

He certainly doesn't sound unhappy! It's possible he's still doing them but you're missing them b/c he probably gets those sudden rushes of energy early morning and very late evening while you're asleep. Since he's not confined he's free to be happy whenever he wants.

My bun does not binky very often either ..... and she too is free range. She seems very happy and content ... and she too lounges around and stretches out all the time. My thoughts are it may be because she is out all the time. I do put Bonnie in her cage at night for safety reasons.
My hubby is clumsy in the dark & gets up often during the night ... so I do not want him stepping on her. Every now and then, in the mornings, she might do a quick run and binky. We have noted when we leave her alone & go downstairs to watch movies ... we hear her running fast around the room .....we can hear her do this from the room below....and she is in the room above us. I guess she likes having the room to herself to play. This is normally late at night too when she is more active.

I would guess he's doing it when you're not around. When we visited my parents over Xmas, they would let the bun out of his cage at 7am - he usually doesn't come out until the evening. They said he would run around and binky like a crazy man, but hubby and I always missed it because we didn't get up until 8am :-P He's usually a big nighttime binkier, but since he was getting them out of his system in the morning he stopped doing it at night while we were there.

I guess bunnies only have a set number of binkies in them a day and your guy might be getting his out of the way while you're sleeping.

Cotton I love to see him race about the room.  It is so funny .    He has been doing it more lately.

Maybe your bunny has matured?  Outgrew zipping around room