rumor has it
The 600r is on it's last legs, probably. While it could stay in production like the Katana, every design gets old at a certain point and they need to grab your attention.
FZ1 and FZ6 are latest updates/replacements for those bikes within Yamaha lineup, as I'm sure you know. They traded in some of the "sport" for a dash of the newer, always popular "naked" in the transition. FZ1 has been a good seller and I suspect the 6 will be too.
Interestingly, what gets lost in the switchover is the adjustable suspension. My 600r has preload, compression + rebound adjustability on both ends, whereas new FZ6 has preload only (?). I definitely prefer the sportier look of the 600R, but gave the FZ1 more than a passing glance before I made the purchase.
YZF1000R/Thunderace was the bike before the R1. Lighter, faster, lighter and faster are the reasons the TA was binned. At it's introduction, the R1 stood out where the TA was ordinary. It represented modern technology (aluminum frame, etc).