i do not think bittrex is competition to poloniex to be honest. polo showed many times that they are the right choice to be the main xmr exchange. also cryptsy just waited too long in my opinion.
Just my humble opinion:
Craptsy has shown a long history of deliberately torpeding all the arbitrage trades one could make there. So my bet is they are quite happy about doing arbitrage trades over there
, themselfes.Shittrex definitely makes one of the trading fee miracles, they are charging higher fees then all other market competitors but seemingly on occasion charge you more then they are officially announcing. You have to look at your portfolio with eagle eyes.
And if any coin has proven to be a real shitcoin, it always happened to be big on volume at Shittrex (hence my personal, private naming of that place)
end of rambling. I'm in a bad mood since the April Foolers over there at BCN just censored my fair warning from their announcement. Some poor soul dropped ~7.8BTC into that 5 Satoshi crapcoin that usually goes for 3sat, or mostly for 2sat. That one will for sure loose one half of investment on "colored anonymous coins" with shiny GUI (release date 4/1/2015)