Judging by the angry chatter online, I guess there must be a large group of people who are pissed and who are suddenly without a place to work out.
Do not fret any further than you already have. Here are some suggestions for you to still get your exercise (and maybe bring your temper down as well)
Tip: Challenge yourself and do circuits, squeeze in sit-ups and push-ups every 400 meters
Tip: Challenge yourself by doing interval runs; sprint every up slope and recover on the flat gradient
The Southern Ridges
Tip: End your workout in VivoCity where you can relax in one of the many restaurants there