I was at the zoo yesterday, and i must say i sure was impressed with the refurb that is happening.
As for the lemurs, they all looked very happy and very excitied to be in the exhibit jumping around and continuously exploring every single spot they could. As for numbers if memory serves me right, there was at least 6 of them, they are certainly not shy either, as they would all come right up to the glass viewing areas and try to interact with some of the people that were around them.