It wasn't that bad. It did require manual intervention to get the install to work (which isn't a great surprise given the nature of the update) but it installed pretty painlessly on all bar one machine. The one exception being a laptop which I put off the update for several weeks and then left myself with a much larger job than it should have been - so really that one was partly my own fault.

The glibc update from around the same time was a much worse update update. I think that one did break every Arch install I had at that time.