Yep, this little 9 month bebe of mine can sign "more"! She frantically waves her arms together in clapping-ish motion to sign more so she doesn't do it perfectly but knows what to do to communicate "more" and I love it. She does it from the time the spoon leaves her mouth until it's back in. :)
And, she loves crawling out onto the balcony to be with her sister. She just mastered crawling back in this morning and can stand with only holding on with one hand.