I noticed that Caesar have upcoming Police Men and Civilian sets coming out soon.
I sent them an E mail asking about Modern Zombie sets this is the reply.
Dear Mr. Wayne:
Yes, we have produced this product. Wait for a while you will see the products soon.
Best Regards, Peter (Caesar Miniatures)
So it looks like their will be some 1/72 plastic Modern Zeds coming out this or next year. This is great news as Caesar are the best producers of 20mm plastic minis