8
We all have different views on this. I personally wouldn't go higher but I wait in happy anticipation of the next release.
Do a search on 2.2.3 and 2.2.4 and you will get lots of comments about this development in the core - make up your own mind. As I am reliant on the expertise of the coders and want as much as possible a problem free experience I am happy to stick with the current recemended version which is what the newspost was about. For me it is about stability.