We use the future continuous, will + be + present participle,

• to talk about events that will be in progress at a particular time or over a period of time in the future,
• to talk about events that will happen in the normal course of things, and
• to politely enquire about a person's plans for the future.

We use be + to-infinitive to talk about future events which involve instruction or necessity.

http://www.bbc.co.uk/learningenglish/english/course/intermediate/unit-22/session-2/activity-3

http://www.bbc.co.uk/learningenglish/english/course/towards-advanced/unit-10/session-1