So I was on the comments page for a circle I'm subscribed to. Sometimes when I upvoted a comment, the ticker increased. Other times it stayed the same. It was completely random. And it was an older post so it was not like my vote was being cancelled by someone else voting at the same time.
I tried an experiment, too--on a comment where I upvoted and the ticker did not increase, I clicked again to withdraw my upvote, and the ticker did decrease. So on a comment that had 3 before I did anything, I upvoted and it stayed 3, but when I withdrew my upvote, it became 2.
I think there's some bug that has been introduced.
Thank you for the bug report, and all your other great feedback today. I'll add this one to the to do list.
In the future if you want to see the features we're working on go to your user preferences (the gear icon next to your user name) and turn on "Enable Experimental Features". Currently there's nothing different there, because we just rolled out all the formerly experimental stuff, but with that checkbox turned on you'll see whatever is coming next while it is in progress.
Oh, cool! I'll definitely take a look.