Same here regarding errors.
But this week, I also saw something that I hadn't seen before (and at level 1062, I've seen a lot). I won a bunch of invades and got the victory screen each time, so I didn't even suspect anything was wrong. But a little later when I looked at the leaderboard, I noticed that I somehow received a loss. Not only that, my 500+ game win streak was reset too. Looking in the battle log, I found the incorrect result (the alleged failed invade was against a simple Ogre/Lance Knight defense that I steamrolled).
I submitted a ticket to support, because this seems like a pretty serious bug with Guild Wars coming up.