Okay, "very convenient" was a stupid way of putting it.  I like "x++"
because it makes me think about the code I'm wirting differently.  It's
not because I'm typing less.  It's because I use ++ in some circunstances
and += in others in such a way that I feel my code sends a clearer
message.
I use ++ for counters and indices, and += when the numerical value has a
greater significance (even if I end up writing "+= 1").

So, I'd like to replace what I said by "I like it a lot".

Still, why doesn't Ruby include it?  You can hardly say it's confusing.

Daniel.