The new Yamaha R6, Honda F4RR or whatever, and Kawasaki ZX-6R are the most exciting bikes to hit this class since 1998. Given that it's the most exciting class of motorcycles going, that's something.
I just joined the ranks of 600 owners, though I bought a less-than-cutting-edge 600, a silver '03 YZF600R because I'm a fat old mouth breather who's into self pleasure to such a degree that he values comfort over performance. But even my old cow of a 600 is incredible fun. Given how good that old design is, this new crop of 600s should be unbelievable.
I don't know if I'd buy once, since I already have a 600, but when Yamaha adopts its aluminum casting technology to the R1, I might consider a two-sportbike garage. (Or if Honda updates the Superhawk...or if Suzuki doesn't screw the pooch and use crap suspension on the SV1000...or if Kawasaki makes the ZX-9R into the mother of all sport-tourers...)
I'm sure some of the new '03 models will disappoint, as did Honda's 954, 919 and Interceptor last year, but overall, things just keep getting better and better. If I didn't measure my life in coffee spoons, I might be tempted to use an exclaimation point.