Got down to Mogo today; wasn't expecting many changes but they surprised me, as they have the last few times I've been. The baby lemurs were darling.
The big change is that the old row of tamarin exhibits at the top of the zoo have been knocked down. The entrance building is now entirely open on this side (out towards the silvery gibbons). I think this is a big improvement - those exhibits, while perfectly adequate, had served their purpose and were superseded by the newer, shinier ones down by the cheetahs, and this opens up this area of the zoo wonderfully and helps a lot with the cafe.
The capuchin exhibit has been cut in half, with the squirrel monkeys now occupying the glass extension and the capuchins in the old half (formerly lemurs, gibbons and, eons ago, puma). At first I was a bit concerned about the capuchins - that's a very small space for the number they have - but it seems that they have full access to an off-exhibit area that is at least as big as the part they've lost, so that's good. Still kind of a dingy exhibit though. The squirrel monkeys, on the other hand, look great.
The reptile house is closed, apparently for good. This is a pity, but it was always a bit of a placeholder and I'm sure Mogo can build something bigger and better if they want to.
The fennec fox exhibit was "under renovation", and the fennecs were down in one of the tamarin exhibits opposite the otters. The other change was that a large troupe of Cottontop Tamarins have moved onto the island that used to house ruffed lemurs, where they make a very effective exhibit.
As triple confirmation for Chlidonias, the binturong is definitely still there.

I only saw one tapir, so they may have lost another of those.