Hi there Ozziworld,
let me put your mind at ease. Kenya is as safe now as it has ever been. In fact due to the fact that so many people are still worried about travelling to Kenya when you get there you will have the parks virtually to yourselves which is a real luxury.
I'm going back in four weeks time (and was even there last March after the trouble and the whole situation had calmed completely).
Your kids will love you forever for the chance to visit this amazing country. It's everything the visitor imagines it to be and then multiply that by 100.
The only drawback of Kenya is in my opinion, Nairobi. Nairobi is not a safe city after dark. Do not travel by foot after dark in Nairobi, always use a taxi. But it's perfectly safe (as far as I've seen) during daylight hours once personal safety is considered(no jewellery, outward signs of affluence, etc., ) and common sense are used.
Besides that, the people are great and really welcoming to visitors, don't forget, tourism is the No. 1 economic generator for the entire country, it's in their interest to look after you.
So go and enjoy, and watch your children's faces as they encounter a lion or elephant for the first time, you can't beat that anywhere.