I got a 2006 TL a few months back. It has been very good so far. I was surprised at how much the women I've had in it love the thing. They go hypersonic when they see the navigation system.
I don't want another car without a nav system, the thing is so freakin handy it's unbelievable. It could be improved, but just as it is, it's great.
The TL is really more about the toys than it is a real performance car. But still, it's nice to drive, good handling and braking. Acceleration is mediocre, maybe slightly better in a TL-S, but probably not that much in reality. It is consistently over 30 mpg on the highway, usually low 30's @70-75mph, with around 24 MPG in town with a light touch on the throttle.
Very comfortable seats for a long trip. I can actually put a couple of full size people in the back seat, as opposed to the midget-gymnasts that could fit in the back of my Mustang.
I got XM radio for it also, I recommend that. I like Squizz, Verge, and the comedy channels. The factory iPod connector sucks. There are some better aftermarket connectors, but I'm having a hard time with allowing some dumbass to disassemble my dash to connect it. I know there would be rattles afterward.
The dual zone climate control is a great feature. It should allow different fan speeds in the different zones though.
There is a little torque steer under full throttle, but it's not a problem in general driving. The car makes up for torque steer with nice space efficiency. I love RWD, but the large trunk and back seat are really more useful in a daily driver. I don't go around racing people anymore anyway.
I'm very disappointed in the styling of the new 2009 TL. It may be a superior car in many ways, but bad styling trumps the upgrades.
My 2006 TL was $24k + TTL with 15k miles, nav and AT about 3 months ago. Your deals will get better the longer you can stand to wait for a 2008, but it's a risk of course that someone else will get the car you want, and they won't be getting any more.