What are the plusses?

That's too creepy!

And also impossible to do.

Yep, they are indeed those 'strange little arrow things'.

Ben

Are those those strange little arrow things? 

And if you click on the actual number between the arrows, you will see the names of those who clicked.

Ben

Well Homebird, I've just liked your opening post by clicking on the mauve 'like' button. I have also 'liked' Tris's reply by clicking on the 'up' arrow.  If I don't like a reply, I can click on the 'down' arrow and the count will go down one, or sometimes into minus figures.

If you play with the buttons on this (my) post you wil see what happens.

Ben

The like counter?