It would be hard to do that because I use a relatively small number of exchanges. At any given time I'm selling 150+ BTC so I can't go just anywhere with that. I can only provide you with the following info that I've built through experience:
1 - In my experience the number of people that want to SELL BTC is MUCH, MUCH higher than the people that want to BUY BTC. And the amounts vary greatly too. So, my theory is that some exchanges are only surviving because they use OTHER exchanges to balance their books. These are known as counter-parties. So I would be careful with smaller exchanges (like CampBX) because at some point they must use a counter-party. If they use MtGox as their counterparty (which surely some exchanges must do) then watch out! Very dangerous.
2 - Regardless, dont trust any exchanges. Even the solid ones I mentioned above (like Tradehill and Coinbase) I would ALWAYS move my funds back to my bank account. It didn't matter to me if it just needed to sit there overnight because I knew I wanted to withdraw again tomorrow, ALWAYS get your funds back the same day. Theres too many potential reasons for these exchanges to close overnight (regulatory, financial, etc) to leave any money just sitting there. Just doesn't make any sense to me.
3 - Stop reading the nonsense about how BTC is the next big thing that will equalize society, bring peace, suck your dick, etc, etc. That is all nothing but fantasy. BTC is a pure speculative tool, its all just a game of smoke & mirrors, nothing more. Realize that it can end at any time and you CAN and WILL lose money at it. I compared my BTC transactions (and I've done a lot of them!) to moving nitroglycerin (1) you do it just a little bit at a time (2) you know EXACTLY where you're going to put it once you have it and then (3) you head back to safety (USD) as quickly as possible.