After using 2.3 for a little while, I just wanted to say that I think it looks great and works great. Although I had some hardware issues, I was able to get them resolved and everything is running smoothly, including the recent 2.3.1_5 update.
My only note, at all, is just that the dashboard is requiring more processing. When I load the dashboard, I can see that the 15 minute load is never higher than .05, but if I leave the dashboard up, the one minute (and wait long enough, 15 minute) load will be between .8 - 1.5, whereas prior to 2.3 the load was usually .4 - .6. So it looks like there is something about the new interface that is requiring more resources from my hardware. Certainly not anything high enough that I am concerned with it, but an observable change.