On IRC, everytime the server crashes there's someone yelling DAMN I WAS TAMING COWS/SHEEP. Could be a coincidence, ofcourse, but still it is weird.
I think that I may have caused today's crash. I was taming mouflons (group tame, 6 of them at once). Everything went smooth as long as the herd stayed together. I got bored though and wanted to show my 2 soon-to-be sheep to the rest of the village (leaving herd area, ? symbol for maybe 30 secs, deaggro coming soon). No lag, no indication of any serverside problems. Then, the moment before getting deaggro - I can only guess so, but the ?s had been shown for rather long - the server crashed.
@Loftar: can you/do you usually retrieve logs of the exact causes of a breakdown? There MIGHT be something broken with the taming AI which in turn breaks the whole server, it could be worth a checkup imho.