I’ve been giving most of the details over on Facebook, but I thought I should nail down this big step in getting our gigabit fiber Internet service. The crew from USI came and brought the fiber from the junction box on the side of the house through to the ethernet switch they installed on the wiring panel.
So far as I know, actual Internet through this is still scheduled for sometime in the first two weeks of June.


Also, note the support for a serial “console port”!

I think those are just labeled as ports 9 and 10. Zyxel no longer seems to document the GS2200 on their website, but
http://www.zyxel.com/products_services/gs2210_series.shtml?t=p
has this for the GS2210, which looks physically quite similar:
GS2210-8
8-port GbE L2 Switch
• 8 x GbE RJ-45 ports
• 2 x GbE combo (RJ-45/SFP) ports
Found some GS2200-8 docs, does look similar to the GS2210.
Those two ports at the *top*, including the one the fiber goes into, are the RJ-45/SFP ports. “SFP” is “small format pluggable” or some such, originally a Cisco standard but now widely described as “industry standard”.
Given that the top and middle ports are *both* numbered as 9 and 10 (you’re clearly right about that), I’m guessing that the real confusion is that “combo” doesn’t mean the two functions are combined in one fitting; that there is an SFP 9 and an RJ-45 9 and that you can’t use both at once (and same for 10).
So, this device can take one big input fiber, and can produce up to 9 1GB copper ethernet ports, or 8 1GB ports and one additional SFP port. They probably would use the other SFP port to deliver 10GB copper ethernet for example (which they do offer; only $399/month).