It's now possible to download a new version (1.19.0) of Second Life by going here. Seems like a lot of things have been fixed.
Today’s Release Candidate Viewer (1.19.0 RC0) contains a ton of bug fixes and re-introduces some functionality that was previewed in our 1.18.6 RC viewer series. As mentioned in our final 1.18.6 RC post, we reverted back to the same XUI-based login code used in Second Life Viewer Release 126.96.36.199. This release also addresses the QuickTime security issue identified back in December (which were originally slated for the 1.18.6 viewer as well) and updates the required version of QuickTime to 7.4.
Don’t forget that Release Candidate viewers are optional updates that contain the latest round of bug fixes and/or soon-to-be-released new features. Please visit the test software page to download the Second Life 1.19.0 (RC0) Release Candidate viewer. Source code will be available for download shortly, too.
Go here to see the full patch notes.