i just traded in my 2000 sv650 for a 2002 919 in june 06. i loved the sv650 but i wanted a little more power. i weigh 240 and am 6'-1". i had seen the 919 at cycle shows and always loved the styling and feel of it. it has a LOT more power, and the fuel injection is great. the 919 feels very slightly heavier (372 versus 427 dry weights) but seems to whip through turns just as easily. im sure the sv650 frame is stiffer, since it is a state-of-the-art frame, but since i do most riding in city and suburbs, i can't feel the 919 frame wallowing.
so, the 919 is much more powerful, much cooler looking, fuel injection much smoother than carbs, easier to start, and seems to ride about exactly the same as sv650 did.