Hey taal,
Isn't it great? The "wet side" is not completed yet. It's immediately to the east of the part that you visited now, or the "dry side". Not sure if you saw fences to the east and large rocks and exposed top soil...that's the part that needs to be completed and should be ready for spring of 2014. It's part of the Flood Protection Landform, and can't be planted with trees but rather grasses and wildflowers. So the park will be significantly larger come this time next year and will stretch behind River City to the King/Queen Triangle, as well.
The large paved area to the south will be developable blocks after the Games, including the development of a possible school. It was just paved within the last week, so it's likely just part of the Games parking or for tents, etc. Paving will keep down the dust, too. Not sure if they will temporarily sod the other development blocks for the Games, but I imagine it will look really decent and not so much of a construction zone by summer 2015 lol.
Hope that helps!