Had a look at the demo today.
Its really nicely done. Spreads are good (seem to be even tighter than on the website sometimes), its got a marketdepth display, lots of ordertypes, easy orderentry and a really convenient visual chart-trading feature.
But if the other firms are going to charge the same commissions as RCG, i guess it wont draw too much attention. A newcomer competes against Interactive Brokers and Oanda and the likes, doesn't make much sense like this, in my opinion.