To address WiFi connectivity issues in the previous gold master build of iOS 4.2, Apple has released a second GM build of iOS 4.2 for the iPad. The previous build number was 8C134; the new build is 8C134b, probably indicating only very minor changes between the builds.
It's unclear how this will affect the public release date for iOS 4.2. The Daily Telegraph reports iOS 4.2's public release may be delayed until November 24, although it's unclear why. If WiFi connectivity is the only issue this new GM build of iOS 4.2 addresses compared to the old build, it doesn't seem like another 12 days of testing before public release is warranted.
Mac OS X 10.6.5 was released earlier this week, and iTunes 10.1 came out earlier today. According to earlier rumors, iOS 4.2 was supposed to have been publicly released today, but the last-minute bugs in the iPad GM build made that impossible. All the other pieces are in place for iOS 4.2's public release, so now it's just a waiting game.