Update 2014.03.07
I have learned about BlackCoin and DarkCoin. But it seems that both of them mining a bit too fast. I am a bit afraid on this.
Could you mean by this? Darkcoin is one of the few coins with genuine innovation, here is an explanation for how it works:
http://razorsforex.blogspot.co.uk/2014/02/darkcoin-anonymous-cryptocurrency.html
It deserves a place on BTC38 not only because it is popular and high volume trade (see it's high trade volume on cryptsy) but also because there is real development going on there. There's no problem with the Darkcoin mining rate. It has a solid supporter base and has kept a relatively stable price compared to many other coins.
Also an announcement about Darkcoin beta testing phrase made it to the 'hot' section in r/bitcoin:
http://www.reddit.com/r/Bitcoin/comments/1zde2w/darksend_beta_is_live_now_drk_darkcoin_the_worlds/
This demonstrates a high level of acceptance of darkcoin's usefulness by bitcoiners, indicating it is a respectable coin and worth adding. I'm sure Darkcoin will be one of the highest volume coins traded on btc38.
Edit:
Also Darkcoin is DRK, could you please correct this in the poll.
+1
+1. DRK is about the same age as most of these coins such as VertCoin. It's popular because it brings something new: anonymous transactions. Most coins are meaningless copies. DRK is already popular on the American exchange Cryptsy and it will likely make it to BTER soon. BTC38 simply misses out on revenue if it delays.