Looking at this area on Saturday, it seemed to me that the only major job left was assembling the 'Baobab tree' slide, as I presume that all the parts for it have been made by now. From the plans I think it will go to the left of the digger. I think they would like to have everything in operation for the Bank Holiday weekend.
The area in the foreground is part of a roughly triangular space next to the lions. This has curved paths and seats for those who don't want to Play! But it might be a bit too noisy for a picnic.
@Water Dragon The building is still there, as you can see above. The lettering on the side says Madagascar Marketplace, which may be a subtle hint about the plans for this area of the zoo