Really? I have a lot of complaints about ChromeOS (I have a chromebook, and nuked ChromeOS off of it), but that isn't one of them. Gigabit connections may be rare in the US, but some form of broadband is typically ubiquitous. You have to get pretty far out into the country before you find people who can only get dialup. Just a few Mbps is perfectly fine for ChromeOS purposes.
I guess I am saying reliable and extremely consistent speed. I mean using that at school is a challenge for a lot of people. I can't get fios yet and I am stuck with this inconsistent, horrible connection that works excellent only after midnight at home.
In general, that's very true for a lot of places in the US.
While I can find a lot of free wifi in NYC these days, they are slow and some of them aren't secured either. So while chromeOS might be secure as OS, I still don't quite trust the connection.