Judging by the numbers, the V5 5500 looks competitive with the GeForce, but I have to wonder if it will really be able to go toe-to-toe with the NV15.
The guys at Beyond3D have also promised to publish Voodoo 5 benchmarks soon, and their server's getting beaten like a Tyson cellmate tonight. Assuming their server can hold up, their V5 preview should be very interesting, because they really seem to know their stuff when it comes to 3D.
Update: The Beyond3D Voodoo 5 preview is online right here. They didn't publish comparative benchmarks, either; 3dfx must've "leaked" these cards early with some strings attached.