1. Tokyo and JFK
are not new routes. Tokyo is only being upgraded. A340s will be used on the Tokyo and Osaka flights, but it is possible to fly to New York without any payload restrictions with an A330.
2. Since Egyptair become a holding company, it is suggested that they will place an order for 2 A340-600s (with a further 2 on option) as they did before they cancelled that order. They may also purchase more A330 depending on how successful they are once they are introduced this summer.
3. About the A330 replacing the B777 or A300. Well it is a bit of both. The A300a are mainly used on domestic and African routes and since Egyptair has received the new A320s they are replacing them on these routes and increasing frequency. The A330s are also 'planned' to replace the B777s on European/Middle Eastern routes. As mentioned in point 2 they might order more A330.
I hope that answers your questions and please ask me if you have more queries