Height is pretty different, though; if you don't tell someone "Hey, by the way, I'm actually really tall," it's not going to physically impact them in any way (and if they decide they don't want to date you because you're tall, the end result is the same, and you dodged a bullet!). Also, it's kind of an obvious physical feature once they meet you and see you standing up (which, based on your post, might be happening soon). If you do tell someone that (as in, drawing specific attention to it with no prompt from the other person), and they don't mind at all, then you could come across as self-conscious or insecure, which generally doesn't leave a favorable impression.
ninja'd