It's mainly Safari was hanging when I had about 6 tabs open. If I switched to a different application then back to Safari it would simply not load the tabs back up and would give me the beach ball.

I had the situation also when I couldn't close down the computer because safari was preventing it as it had locked up

Lightroom when I came back from a trip was misbehaving, wouldn't close, wouldn't open after I managed to close it. This was with about 1200 1MB images in the catalog

MS Word was being a pest but I did have a document open with about 10MB of images embedded in it

No problems right now, I have 355 images loaded into lightroom and it is starting up in a flash. I really do think the caches folder might have been a problem, I thought onyX had deleted it but apparently not