Many thanks to Level3 for the quick response ... naturally, as soon as I
posted, the problem disappeared, and everything looks fine at the moment. :)
(I'd almost rather have something stay broken than to mysteriously fix itself
...)
You can also check lg.level3.net. It allows city specific tracing, ping
and bgp queries. You could relatively easily determine in-real-time
whether its "just you." Hope this helps.