FIOS followup
So, Verizon came by on Monday to install FIOS. Although the nominal throughput is the same as that offered by the cable company, the latency seems a lot lower, and packets spend a lot less time rattling around the ISP's internal network, with the result that doing Internet stuff with FIOS feels a lot faster than it did over cable.
At the same time, we took advantage of the opportunity to do more cleaning and organizing in the basement - we had to, really, so that the Verizon tech could get into the corner of the basement where the wiring came into the house. We made a lot of good progress there, though there's still plenty to do.
Finally, the home networking setup is a lot saner. Previously, my (downstairs) office used a pair of Airport Extreme base stations connected by WDS to get to the Internet uplink (previously, the cable modem in the upstairs living room). This had a number of problems, in-house bandwidth being one of them, and a hostile 2.4GHz environment being another. For example, I was unable to use my Bluetooth earpiece in the house, because (as Glenn Fleishman so helpfully explained) Bluetooth 1.1 doesn't frequency-hop around the part of the spectrum used by Wi-Fi, with disastrous results for both, in the case of an access point and a Bluetooth pair in, say, the same room.
So, another project that was undertaken in advance of the FIOS install was to pull an Ethernet cable from the living room down to the basement. The placement was fortuitous; the corner in which everything happens is the same in both rooms, so it was a simple vertical drop. My future father in law did most of the hard work while I assisted, then I terminated both ends of the wire in a socket and wall plate. (I used the Leviton QuickPort connectors and wall plates, and they worked great.) So, now there's a high-speed (1Gbps) link from downstairs to upstairs. (In retrospect, I should have pulled multiple wires since that would have afforded more flexibility in the future, but if I feel ambitious I should be able to do that at my future convenience — and when the addition goes in, it'll probably happen anyway.)
A 5-port Netgear gigabit switch next to the router provides switching isolation for the internal LAN, so that gigabit devices don't get bottlenecked by the router's own switch (which is 100mbps). Another 5-port gigabit switch in my office is connected to the main switch, as is a 100mbps switch for the various networked printers, and upstairs an 8-port Netgear gigabit switch provides switching isolation for the machines upstairs, including the Airport Extreme base station which serves the wireless devices in the house. (And yes, even with all those switches, the network topology is much simpler than it was before the wiring was done.)
The upshot is that all of the fast machines on the wired LAN can talk to each other at full speed, regardless of whether they're upstairs or downstairs. The SqueezeBox in the living room no longer bogs down the LAN by saturating the wireless network. And I get to use my BlueTooth earpiece again — as long as I'm not sitting next to the AirPort Extreme in the living room...