Yes they have center tanks, also some have aux tanks as well. To go from Houston to Boston, there would be a lot of fuel in the center tanks. I don't have my manuals anymore, but even in a corporate configuration, they could be heavy depending on how much fuel they loaded...tankering, etc..
As a pilot for an airline with TV and internet on our planes, we are actually discouraged from making anything other than a welcome aboard PA. The rationale is that passengers don't want the TV audio interrupted for a sightseeing update. Also, if they're curious about our position, we have a moving map channel. I used to enjoy the updates, but now I just enjoy my view.
The runways were fine, the taxiways were awful. We landed 27 and took the same taxiway 15 hours after this incident and it was still an icy mess, as were most of the taxiways leading to our gate.
