This is a stable update to incorporate some fixes from r251. Since r250 was released last month, we've had some reports of crashes on startup. There were also some issues with event sheet dialogs taking a long time to open in large projects, which possibly correlates with a Windows Update that went out recently. Both issues ought to now be resolved; in both cases we've had confirmation from multiple users that it is working better now. This update brings these improvements to the stable channel, particularly since the crash on startup is a serious problem.
In case you missed it (or you couldn't update to r250 before), you can check the r250 release notes here. There were many improvements, particularly around how Cordova exports work now.