Yes, anything that results in a stack trace with "abnormal game end" and a link to return to the lobby shows up in the logs; generally you don't need to report those. (It doesn't hurt, though, and ensures they don't get missed.) For instance, today so far there has been:
Tue Jul 23 06:20:16 2013: CRASH game-69: lost card(s) [], gained card(s) [<Canal Building 40e22dcc>, <Rocketry 42033f8c>]
Tue Jul 23 07:35:48 2013: CRASH game-123: 'supply'
Tue Jul 23 10:51:32 2013: CRASH game-240: unsupported operand type(s) for +: 'int' and 'NoneType'
which resulted in fixes to Kim Yu-Na, Tuning Fork, and Toothbrush, respectively. (Will be out with next server restart.)
The ones I really need reported are ones where it doesn't result in a crash. For instance, Pele's win condition is currently broken. It doesn't crash the game, it just doesn't happen when it's supposed to. (Also fixed with next server restart.)