Not sharing spoilers, but the new season is starting on August 23 for the US (8 pm ET), Canada, the UK (obviously) and other places too. They are doing a world tour and the first will be in Cardiff. During that event, they get to meet Jenna and Calpaldi will be able to see the first episode of the series in early August. Of course, they will be going to other places outside the UK on other dates, but no Comicon.
Of course, the really insane thing going on in Whofandom is the leak, again there was a HUGE leak of the first five episodes of the new series. Somehow they were at the translators in Miami and the scripts were posted in full. The BBC and others of course are upset, which is very understandable, but I'm amused as the idea they would post these things on an non-secure server is a bit daft. Then again I just read they accidentally leaked the last episode of last series on Blu-Ray before it aired, so I guess this is sort of par for the course.