Undoubtedly individual experiences vary; in my case I have to say kudos to Adobe. After my initial update to LR CC/6.0, after hearing about all the problems people were having with the early July update, I stayed put and lived without the haze filter or the B and W controls in the adjustment tools.
Once 6.1.1 became available the other day I took the plunge on the presumption that Adobe would have by now addressed most if not all the issues that users previously identified. (It had to be a presumption because they wouldn't provide me the list of bug fixes - see post above.) Meanwhile, over the month of July, every day the Adobe Updater application dutifully nagged me to update, and I dutifully ignored it until Thursday morning.
The CC Updater application updated seamlessly, and the subsequent downloads and installation of both Photoshop CC and LR CC 6.1.1 also occurred seamlessly. I downloaded Photoshop first, using the option to retain the previous install, and that worked fine. The Lightroom update however did not provide the option to retain the previous CC version. (So now I have on my system only my "perpetual license" of LR 5.7 and the latest CC 6.1.1.) However, that turned out to be a non-issue, because the new install is fine. It picked-up my latest LR catalog correctly and the application opened exactly where I had left off from the previous usage. As Wayne noticed, I too see quite a dramatic improvement of application responsiveness; for me it seems to be for all tools using the GPU-enabled option. Everything just responds faster and more smoothly. And my GPU is five years old (ATI Radeon HD 5870 1024 MB).
My computing environment is a Rogers High Speed Internet Broadband connection, MacPro mid-2010, 24 GB 1333 MHz DDR3 ECC RAM, 2 x 2.66 GHz 6-Core Intel Xeon hyperthreaded (24 virtual cores), 2.66 GHz, and 2TB Hitachi internal system drive; OSX Mavericks (10.9.5). It's all out of date, but very performing.
