The next Apple press event is October 22nd. iPad-centric, but also expected to include Mac Pro pricing/availability, so probably Mavericks release as well...
I hope to hear some news about updated MacBook Pro's as well!
I just hope for a Retina Cinema Display... but will settle for a Cinema Display with MagSafe 2, USB3... maybe a small res bump?
I expect it will be released on the 29th of this month given that last year Apple released Mountain Lion the day after their earnings call.