NUTS: RedBack seems to have a solid community and professional affiliations, which should inspire confidence among the players. Their 110% up to $600 first deposit bonus is a nice offering. It's doled out in $10 increments, which makes it much more accessible to those not inclined to grind out the entire amount. Mac compatibility is supported through PC emulators, which is a nice addition. Their wide variety of banking options should allow for everyone to find a depositing path which works for them.
BEATS: Their site itself seems to indicate that the games will be more challenging, which is not a great way to draw traffic. The aesthetics alone, however, can prove to be a stumbling block for potential recruits. Their website is much less helpful than it appears at first glance. And who the hell wants to play on a poker site whose mascot is a poorly drawn black widow spider?