If your willing to invest in more lens than just the kit, take an online or community photography class, or learn yourself through trial and error(which you'll do a lot of with a class)then go for the XS. I learned with a G-series camera for years and the jump to a DSLR was not that much of a hurdle. It would have been harder had I not played around with the G2 for so long, but you have a point and shoot to fall back on to make sure you get a decent photo.
I currently own a Canon PowerShot SD750 Digital camera, I had it for almost 1.5 years now, and I feel very comfortable with the camera, but now I want to upgrade to something that gives me more functions. So, I was thinking of either getting a Canon G10 or Rebel XS. I don't mind the weight of the DSLR camera since I will still have my SD750 if I want to go portable, but I am just afraid that it will be too much for me to handle (skills wise), so I don't know if I should go with something like a Canon G10 first, to sharpen my skills before I invest in a DSLR camera.