No issues here.... I think the reddit OP was probably just impatient. Occasionally, I get a buy/sell order that may take longer to confirm in the blockhain with them, but overall it's not that bad. I think they've been testing the # of confirms over the past year on what's reasonable vs what's safe. Like all software and systems, there will occasionally be issues. My experience with coinbase has been top notch, in both technical support and service. I started with Gox (booo!) and then moved to BTC-e, which is ok too if you can read russian and spend all day finding cash cards that will work in latvia.
Sticking with coinbase here....