Low latency forwarding failure detection

Not receiving any response for over a week after posting this query to
cisco-nsp I thought perhaps folks here might have some input. In my
scenario, Cisco is the likely gear involved, but even if people have
vendor neutral feedback about this I'd be interesting in hearing it.

I've used GLBP, and I was pleasantly surprised at how
well it worked. Certain types of failures were
hitless, and non-hitless failures were still pretty
fast. I'm not sure if it's fast enough for your
application, but I thought it was great.