You got a good voice :D
On the clip it sounds like you're using your "head voice" - we have "head voices" and "chest voices". The head voice is what we use to sing falsetto and soft passages (or just quietly so as not to annoy the neighbours!). The chest voice uses our full lung capacity.
You only get "full" power when you fill your lungs, open your throat and "sing from your chest". As you get more practised, you can get more power into your head voice when you need, and also increase the range over which the two voices merge.
When you first start experimenting with full lungs and the chest voice, you'll think "but I don't want to sing opera!!" - don't worry, once you've learnt to control the column of air (and make sure it's always there) you can sing whatever style you want with damaging your voice.
Full lungs = lots of breathe = confidence = in tune = better control = happy singer/audience
Like Hamfist says: you've got a good vibrato and in tune - that's well over half the battle, it means you've got a "good ear" already. You've also got pretty good phrasing (rhythm of the words, pauses) - that's very good, it's what makes people "singers" that we're prepared to listen to.
If you want the rocky growl, you'll be able to do develop it - but you need to use your chest voice (which you might find a bit intimidating because everyone will hear it in the next street :lol:). And don't push it too soon, just let it develop naturally. Bono didn't have it early on, no one does, it's something you develop from having to sing loud over a band.
Keep at it :D
EDIT: 38th has posted while I was writing - I agree with him. With the basic voice you have - you can almost go whichever direction you want.... unless you have the problem I had when I was young: I wanted to be Janis Joplin or Elkie Brooks - but I'm a boy :( :lol:
