What is the difference between “I will wait for your call” and “I will be waiting for your call”?
The first tells what you will do. The listener will think of the entire waiting period as a summarized action.
The second describes what you will be doing (a process). This invites the listener to think of each moment in the waiting period as it happens. In this case, the person waiting seems more concerned about the call. We can even imagine him pacing up and down as he waits.
Further readings:
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