no OS X 10.8.3 release?
It will happen but it's a bug fix release, not a "Galaxy S4 killer."
Apple will operate on its own schedule. There's no sense trying to upstage tonight. The blowback from the WSJ article was probably enough negative publicity for Apple right now. Any "counter" move would be seen as desperation. Remember, the iPhone 4S outsold the Galaxy S3 last quarter, so Apple doesn't need the latest and greatest all the time to sustain sales volume.
I do wonder if the management shakeup in October has delayed OS X 10.9 and iOS 7 at all. By this time last year the Mountain Lion beta was already in high gear. I think a lot is riding on iOS 7 and this year's WWDC. It's doubtful we'll see a 5" iPhone ever (and certainly not this year), so it will be up to the software and internals to sell the 5S.
It remains to be seen whether Samsung's Eye Scroll is genuinely useful or mostly gimmicky like NFC (i.e. makes for good commercials and demos but not quite a game changer). If it's the former, I wonder what Apple has planned for iOS 7.