Took my 98 TBS in for the 6000 mile service.
As some of the folks here had said, Triumph has indeed extended the valve check interval to 12K on the triples, and so I passed on it as advised by the service manager. I had already changed the oil and the brake/clutch fluids, so I passed on that portion of the recommended service as well.
I did have both fork seals replaced and new oil put in since I had one side leaking, and had the radiator serviced. I had the rest of the recommended services done as well (carb sync, chain checks, etc.). I told them to go ahead and change the plugs on the bike while they were in there since it was cheap.
The bill was something like $460, which is pretty consistent with what I've been hearing from other folks. A stiff price, but at least it was completed quickly.
So, she's back home and ready to go. I can't wait! It's been a really long time since I've ridden it due to a couple of the service items needing to be done. I'm pretty excited.