Update: DCYanks21 posed an interesting question, asking if Montero will be eligible for the postseason roster. My understanding is that he will be, as long as the Yankees try to trick the system by putting Reegie Corona or Colin Curtis on the playoff roster, only to replace them with Montero.
According to multiple outlets, including Joel Sherman and Buster Olney, the Yankees will promote Jesus Montero to the major leagues tomorrow when rosters expand. The Yanks could use a C/DH type of player (they could have used one most of the year) and Montero fits that bill.
No word if he will play in the finale against the Red Sox tomorrow, but it wouldn't surprise me if the Yankees delay his debut until a home game in the upcoming series vs. Toronto.
I will be at the game on Friday, so if he makes his debut then I will have the inside-the-stadium reaction.
Either way, it's Montero time. I declare September 1st, 2011, Jesus Montero Day.