I did a little "unfURLing"* and discovered that the big sale for all the June/July/August Fenway tickets will be 1/26/13. It's showing noon, but maybe that'll change to 10 am. And the urls for the September games say they will go on sale tomorrow at 10 a.m. along with the April and early May. It's good to have these ahead of time just in case they don't put the links up until the last second. Usually they appear ahead of time though. So finding them now might not have helped me that much, but the big finds were the general onsale date and the confirmation that September will go on sale with April/May as usual. Still don't know why they try to keep that a secret every year.

*Wasn't too hard. If you know which of the tickets.com teams have already gone on sale, you just use those urls and start adding numbers till you reach the Red Sox section. I haven't found the Sox Pax urls but I found all the individual games--once you find one you've got 'em all.