its about $200 a month. i get mine for free tho because i work in the industry if you think you could make good use of it it is definetly worth the money - live prices and news and charting etc.
interestingly enough however it may be a bad thing for your trading - you may get caught up watching ticks and lose your positions too early or you may buy in on hype more often etc. so be prepared to go through a bit of a learning curve in terms of controlling yourself - thats what happened to me lol