I woudn't say they're shit, it just depends on your perspective.  I think there's enough profit potential in the exchanges that I created my bot.  That would imply I don't think they are shit.  I have to hold inventory of bitcoin and USD, so I'm unfortunately forced to be a speculator when I don't want to, but I've accepted that risk for now.

The TL;DR version would be that I'm astounded at the level of trust this forum has with the major exchanges.  They just assume they'll do the right thing in the face of tremendous temptation.  I mentioned frontrunning in my last post, but MtGox could fix price at it suits them and the rest of the exchanges would follow.  That makes frontrunning look mild.  They could also come up with clever ways to have market-mulligans by rolling back trades  .

If anything is shit, it's the mentality of this forum.  That you're a hater if you question the exchanges or point out obvious flaws.  I want bitcoin to work as much as the next guy, but that doesn't mean I'm just going to ignore obvious hurdles and opportunities for unethical behavior.  As they say, absolute power corrupts absolutely, and right now MtGox has that type of power until some other exchange can draw a large share of the market.