I am going to do a test upgrade on my dev site this weekend, then maybe I'll know better. I just inventoried my add-ons and only two have been updated for 2.3 but most of my add-ons are nice-to-haves, not showstoppers, so can be left disabled until updates come. Right now, I don't see a lot of added value for us in the new features of 2.3 so if it needs a lot of work or I hit some kind of bugs, I'll put it on hold for 2.3.3 or later. There's no rush for us.
That said, 2.2 is out of support now so I will upgrade sooner or later.