Well...
You're lucky that one of my specialties is dubstep. First, you're gonna wanna stay FAR away from that square bass ya got, get some more of the tearing stuff (this involves heavy distortion on detuned saws). Next, you're gonna wanna play with a lo-pass filter of some sort, to get it going at the rate you want.
Your drums are also strange for dubstep. Usually, they're not quite as busy as you've got. It also sounds like there's parts of the song that aren't lining up; are the patterns even correllating at certain parts? Also, it seems that other parts are coming in at random...I'd work that out lol.
Back to the bass: It's also usually not as busy. It typically stays on one note for a a long period of time before switching (this is why dubstep can get boring, unless you have some way to back it up with ambience or some sort of melody). While you're heading in the right direction, I'd highly HIGHLY recommend listening to some of the pros (look up Nero, Funtcase, Bar9, Black Sun Empire, Tek-One, and Mt. Eden on Youtube...you'll see what I mean). One final thing on that bass: It's usually a minor key, and extremely filled-out.
Back to the drums: The snare isn't a straight-up clap per se, but it's slappier than the average snare drum. The kick is also usually snappy, backed up by a beefy sub-sine or rich tone (I'd recommend getting the Subatomic VST and adding it to an acoustic kick, this is what I do). You seem to have your hats in the right positions...I can't tell if they're playing with the kick and snare simultaneously or not, but if they are, just use the hats for filling it out.
Now, onto your song structure: A TYPICAL dubstep song (just to get the idea, I don't recommend doing this because it can make you sound like mac n cheese) has these specific parts, in this order:
-Intro
-Drop
-Chorus/Instrumental
-Melodic Expansion
-Interim/Break
-Repetition of the intro
-Another drop
-Reptition of the Chorus
-Conclusion
I dunno if you're familiar with the drop, but it's one of the most important parts of the dubstep song; basically, what you do is you build up all this energy in the intro, climax it to a bar (many artists take away all instruments save for a defining line that's usually the title of the song), and then pound out the basic ideas behind your theme.
As it stands, your song has too much empty space, is too busy, and needs a few mastering/structural kinks to work out. You're in the right direction, and it's exciting to see someone that's interested in dubstep. The most important things you can possibly do is experiment with your sound, listen to the professionals, and practice the technique. This isn't stuff you're just born with lol! Keep it up man, and I wish ya luck. If you have any more questions concerning dubstep production, just go ahead and ask me...
And, if you don't think I'm legit in what I'm telling you, the truth is I may not be the most experienced artist here producing dubstep (I only started trying to make it in October 2009), but I've learned quite a bit. You can even check out my dubstep WIPs if you don't trust me lol. I honestly don't care, just know that I want save you (and everyone else) a ton of time by helping you get on the right track...and I think that's what you were asking for lol! So, don't be afraid man, I'll hear you out, Lord knows I've already helped several people get on the right track.
Don't mean to be a braggart lol. Good luck man, keep it up!
-Jazzman