For example I was having problems with a payment in Google Wallet for something off the play store. I was able to ring them, speak to someone from America and get the problem resolved in under 5 minutes.
Two Nexus 7s I ordered for Christmas were not delivered and then returned to sender without contacting me. Google not only sorted this out within a day or so, I spoke to people on the phone and by email with a quick turnaround.
I've heard many horror stories, but I just wanted to add that they're definitely not universal. The fault was not with Google but they still sorted it out to the best of their abilities within a day or two.
In a way, that they do so many things right makes the terrible support harder to swallow ;)