Revenue Forecast is a super useful component of the Opportunities module. It allows you to segment the total value of the Opportunity into expected revenue periods. For example you might sell a package to a customer, expecting an income of 50% at the start of the project and a following 50% on completion. You can split those amounts in the Revenue Forecast section. This FAQ explains the feature in more detail.

This latest update allows you to use the Probability and Weighted Amount frm the parent Opportunity and apply them to all your Revenue Forecast rows.