What happens if I re-invest my money in a retirement fund with my new employer?

No tax, unless you transfer from a pension fund to a provident fund
You cannot make any withdrawals until such time as you leave your new employer
You can cash some of your savings now, but you may have to pay tax on the cash you take
Your savings are subject to the rules and provisions of the new fund. Your new fund negotiates with the service providers and investment managers on your behalf. You can only invest in the portfolios available in the new fund
You and/or your employer contribute according to the rules of the new fund
Your fund negotiates on your behalf with all service providers. Economies of scale help reduce costs
No minimum requirements are applicable