Well, got the saw unpacked, getting it unpacked in the back of a Grand Cherokee when it's turned on its side (had something else in the GC so there wasn't room to put it flat) wasn't fun, but I managed. Got it downstairs and now it's time to take a break.
Didn't notice until I had it completely unloaded that the model number is TS 36*6*0, not TS36*5*0.
I'm betting that the number reflects the new packaging that has the fence in the same box with the rest of the saw rather than any mechanical changes.
The packaging is _real_ nice. The fasteners are all on a bubble card with each type labelled as to size and quantity, and they're oriented so that you can actually count them without opening the bubble. Everything is in fitted foam. Box weighs a ton (well, not really--it's listed as 301 pounds).
The heavy pieces are the base and table assembly (the base comes with the table already attached), the motor, and the table extensions. I can carry the base but it's awkward, I'd be nervous with it on stairs (I skidded it down). The extensions and the motor I can carry easily (one at a time) but if I carry them any distance I know I've been working (of course that might have more to do with being an old fat guy than with their actual weight).
One immediate impression, the blade wrenches that come with it appear to be identical to the ones that Sears sent me as replacements for the ones that came with my Craftsman RAS many moons ago. Don't know if that has any significance or not with regard to origin.
There's a dust port under the blade, it's 2-1/2 inch though. At some point I'll probably cobble up a 4 inch but that's not urgent. I seem to recall dust collection being a criticism of the 3650 so that might be new with the 3660.