Living in South-Africa, I cannot help but worry. I do see this as a positive though as turmoil often sparks a period of cooperation and revival. Zuma will try to intervene as Mugabe is a personal ally. South-Africa's military is too weak to be able to effectively do anything...
If I was president, I would use this opportunity to take control of Zimbabwe. Not a full annexation but at the very least a puppet government that could help restore the country...