Tonight there was a big update in Fiji including OSX specific parts (from a glance at the update panel, btw is there a post somewhere describing this?). Once done, my Fiji install was set to ~4.5 GB memory so the first big task I did caused an out of memory error. I set it back to 14 GB (I have 16 GB total on this computer) but the setting is not retained, and when I restart Fiji it is back to 4.5 GB.
Luckily I had a backup version of my install from a week or so ago so I could revert to this. Does anyone else see this problem too?