Release planning is simply the act of determining what functionality you’re going to be able to deliver in a certain time frame. Obviously you want this data to be as accurate as possible. The greatest accuracy is gained by basing the Velocity on actual historical data.
However, human beings are imperfect, if you simply take a single figure for your Velocity your release planning is likely to be in-accurate. Using, for example, the three, five or seven averages from the Velocity Report will produce far more accurate results.
Then you can evaluate your release plan using the following system.
PBI’s in Zone (A) you’re almost guaranteed to get.
PBI’s in Zone (B) you’re very likely to get.
PBI’s in Zone (C) you’ll conceivably get, but it’s not likely.
PBI’s in Zone (D) you’re guaranteed not to get.