http://www.mlbtraderumors.com/

The above dates are confirmed. On the unconfirmed side, there is word that the Rule 5 draft may be moved to November 20th. The Rule 5 draft typically marks the end of the Winter Meetings, but that gathering takes place from December 6-9 this year in Lake Buena Vista, Florida.
The goal here, according to Stark, is to lengthen the offseason free agent negotiating period, resulting in fewer unsigned players in February and March.