Today I had a chance to ride with a buddy who has a new '04 R1, and we briefly swapped bikes so I can compare it to my ride on a back-to-back basis.
My bike is a '02 954 w/Arata full system, PCIII
w/Dan Kyle map and damper.
The new R1 is very smooth and quick reving. Seat is Yamaha soft and comfortable and ergos are at least as comfortable as my 954. The exhaust note is surprisingly "growly"--like a medium sized dog. I did feel like it was a boat or something the way it reved and sounded. It feels thinner that the 954 and possibly a bit quicker on turn-in. The midrange is fine, but not "pin your ears back" until you reach about 10k rpm. I did not get on the bike hard as it was not my bike, but I did hit about 100 (we were in a remote area with no cross-roads, etc.). The wind screen is basically non-existent. It did feel solid and reasonably stable--but maybe a bit stiff--not suspension, but the frame. The instrument cluster is not that easy to see, and small. Turn indicators are green, just like the neutral light. The bike is obviously powerful in the top of the powerband, and it revs very quickly to the top.
Each bike other than your own always takes some getting use to. However, the new R1 is a good quality piece and, in the hands of someone capable of riding a liter bike like a 600cc bike, it will be blistering fast.
That said, I would not trade my modded 954 for the R1. The 954 with the ARATA and Dan's map just pulls like a rhino everywhere in the powerband, and the 954 chasis feels rock solid. I never feel like the front wheel is going to launch, although I could launch it if I wanted to do so.
Bottom line: the new R1 is a great bike; but I will wait to see the cbr1000!