For some reason, it's gotten even worse for me. I'm currently on 9 opponent's disconnecting on me in a row.
The most infuriating of which was a Japanese player with a rating of over 1830 (I'm on 1821). We played out a great match in which he got three burns from Scald in his three uses of the move, two of which were on physical attackers of mine. This player also got a double Protect towards the end of the game, but then after my first stroke of luck in the match (my opponent's Politoed hurt itself in confusion, from my DynamicPunch on the previous turn), they disconnect when I had the game won. Hail was in play, I had Thundurus and Machamp out, against a Kingdra with less than 6% HP. The game went on for a good 15 minutes, as well.
This is one that royally pissed me off. It was still a good match despite my opponent getting the majority of the luck, it was relatively close, and our ratings were relatively close. But people still can't seem to take a loss and just ruin the whole experience.
If I had a good camcorder, I think I'd literally make a Youtube channel with the sole purpose of pointing out GBU DCers lol.