Viewers
The Main Viewer has jumped up to 3.7.17-294959. This is the new Login Viewer with some maintenance fixes mixed in.

RC Viewers
Maintenance Viewer version 3.7.17.294943 – Minor fixes and additions. I’ve listed them before.
Second Life and Virtual Worlds
The Linden made series of viewers
The Main Viewer has jumped up to 3.7.17-294959. This is the new Login Viewer with some maintenance fixes mixed in.

Maintenance Viewer version 3.7.17.294943 – Minor fixes and additions. I’ve listed them before.
The Oculus Rift Project Viewer has been upgraded 3.7.18-295296. Along with the upgrade comes a post in the blog: Oculus Rift DK2 Project Viewer Now Available. They are still careful to point out that this is a somewhat incomplete viewer, but then Oculus Rift is incomplete. However, those with DK2 units can play with this viewer.
The main viewer is 3.7.17-294959

A Maintenance Viewer version 3.7.17.294943, which is on the Alternate Second Life Viewers page. You can read its release notes here: 3.7.17 Release Notes. Fixes and improvements are:
Login Viewer version 3.7.17.294959 – Release Notes – This is the viewer with the new login screen.
EXCITING NEWS! The HTTP Pipelining Viewer will be going to RC Viewer status as soon as it completes the Lab’s internal QA. Expect it SOON, but not this week. And expect some impressive changes. Monty Linden is calling this viewer the Drano Viewer.
Whirly Fizzle is in Europe and ran some tests. She cleared cache (between each test), and then logged in. With the standard non-pipelining viewer the 105k item inventory took some time to load.
Second Life 3.7.16 (294015) Sep 10 2014 11:08:26 (Second Life Release)
Then again clearing cache between each run and switching to the new pipelining viewer:
Second Life 3.7.17 (294571) Sep 26 2014 12:32:36 (Second Life Release)
If you are measuring load time, you can get exact numbers from your viewer’s log file. Look for “LLInventoryModelFetchDescendentsResponder::httpSuccess: Inventory fetch completed” in older viewers. In the pipelining viewer look for 2014-10-08T23:00:22Z INFO: idle_startup: Inventory and 2014-10-08T23:25:38Z INFO: LLInventoryModelFetchDescendentsResponder::httpSuccess: Inventory fetch completed.
The main channels did get a roll out. It was the package running on the RC channels for the last 2 weeks (38 & 39 or 39 & 40 depending on how you count weeks for rollouts). This was the package with teaks to the Experience Tools project. It also included some bug fixes.

The RC channels all got the same package. This is a package that fixes a problem unique to the Skill Gaming regions.
The Lindens have a new post in the SL Forum titled: An Update on Several Improvements to Second Life™ (9/30 9:36AM SLT).
The first thing they mention is their changing the viewer from using a list of graphics cards to determine what settings to use to using a benchmark process to test the installed video card. Based on the tests they estimate what the card is capable of doing.
The viewer that has this change is a Project Viewer and can be found here: Second Life RC Viewers. I would call this more of a beta version than an RC version. Whatever it is, the Lindens could use some help testing it, especially if you have one of the newest video cards out.