The Sage MAS 90/MAS 200 year-end webcast from December 2010, presented by Tracey Brinkman, covers essential updates, closing procedures, and helpful hints for various modules such as accounts receivable, accounts payable, and inventory management. It specifies the retirement timelines for versions, notes backup and retention strategies, emphasizes pre-reconciling accounts, and provides checklists for each module to ensure a smooth year-end processing. The presentation concludes with resources for support and answers to frequently asked questions regarding year-end processing.