I am sure that, by now, Lightroom users will be aware that Adobe has released new versions of Lightroom, including the desktop version Lightroom Classic CC which is essentially the next upgrade to Lightroom 6. Lightroom CC has now moved entirely to subscription-based model.
The main purpose of this post is to provide a word of warning to users of Lightroom 6 who want to try Lightroom Classic CC. While I understand it is possible to install the Classic CC version alongside Lightroom 6, the default installation mode is to overwrite earlier versions of Lightroom. While this may seem obvious with the benefit of hindsight, I downloaded the new product with a view to seeing what improvements it offered over version 6, and did not pay enough attention during the installation with the result that it replaced my Lightroom 6. I became aware of this when my Lightroom 6 icon disappeared, and when I clicked on the new icon the first task that Lightroom Classic CC tries to do is convert your Catalog to the new system (Classic involves a new raw processing algorithm). While I didn't try it, I suspect that once converted you will no longer be able to use the Catolog with Lightroom 6 any more. If you convert to Lightroom Classic CC, you are only provided with a one week trial period before you have to start paying.
I was able to reinstall Lightroom 6 from the downloaded file I obtained when I first bought the product. This installed the base version (6.0) which found my Catalog and various Collections fine, but needed to be upgraded to work with my camera files. With a bit of searching I was able to find a page on the Adobe site which provided downloads of the various upgrades, with the result that I was able to get version 6.12 back and working relatively easily and uninstall Classic CC. Earlier versions of Lightroom appear to be downloadable from this link: https://helpx.adobe.com/lightroom/kb/lightroom-downloads.html. However you will need your original product key.
Others may have had different experiences but I thought I would bring my experience to people's attention to avoid them falling into the same trap that I did.
There has been a lot of controversy on the Web about Adobe's abandonment of perpetual licences for a one off purchase price. In Australia it's about $15 per month. I have not decided whether to upgrade, although I suspect I will because I make use of the Lightroom key word and file management system and am also very comfortable with the Lightroom workflow (and have invested a lot of time and effort in learning the product). However, I am still evaluating alternatives. The nearest 'professional' product which offers similar capabilities including file management appears to be Phase One's Capture One Pro. I have been playing with this on trial but it handles its cataloging somewhat differently and I have not been able to get comfortable with it. Also while it converts Lightroom catalogs this conversion process only carries over certain processing eg it does not include any local adjustments. On the other hand, its basic raw processing is very high quality with lots of detail, and its use of layers for local adjustments works well and is fast (in my view, one of Lightroom's main weaknesses is the way it slows down when one uses brushes and masking extensively). Also, the one-off purchase price of Capture One is about two year's worth of Lightroom subscriptions, and two years is a long time in software development! There are other products out there in various stages of development for those who are anti-subscription but I have not tried them.
Simon