This is an odd dream in that it is not in need of interpretation, since in the dream, the Odysseus-eagle does the interpreting. After the fact, Penelope wonders if the dream were a fake dream from the Gate of Horn, rather than a true dream from the Gate of Polished Ivory. Scholars debate the role of Homer in the creation of these gates. Was he the inventor or did he appropriate gates from Egypt/Mesopotamia?
When the Odysseus beggar says Odysseus will return is a point of scholarly debate. It is possible to interpret it to mean that Odysseus will return the next day, in which case, he will be in time for the contest. If he does return, she won't have to marry a suitor, but can keep Odysseus as her husband.
It's in this book that Odysseus' heritage from sneaky, thieving Autolycus, son of Hermes, is revealed.
"Penelope and Odysseus in Odyssey XIX," by Philip Whaley Harsh. The American Journal of Philology, Vol. 71, No. 1. (1950), pp. 1-21.
"Penelope's Dream in Book 19 of the 'Odyssey'," by Alexandra Rozokoki. The Classical Quarterly, New Series, Vol. 51, No. 1. (2001), pp. 1-6.
