I run XOOPS 2.2.3 as well as 2.0.13 on a number of sites, but it depends on what my needs are.
The earlier version is amazingly stable, and will support a lot of the modules right now.
The latest version is still a bit new for all the modules to be updated, and some developers are even waiting for 2.3 before updating their modules. So it really makes a difference which modules you plan to utilize.
I like both, but for different things.