This book is written by Dr.S. Sundaram( a devoted Vaishanvite and a retired professor from Vivekananda College, Chennai) and is a detailed commentary (explanatory notes) on the sacred "thiruppaavai" (திருப்பாவை). It consists of 600 pages and will be a valuable addition to your bookshelf.
If you buy this now, you can finish reading by December and be ready for the Margazhi mAsam. A wonderful opportunity to grasp the literal and philosophical meaning of all the pAsurams.