In fact, most modern airplanes (especially jet
fighters) are fly-by-wire.
But only recently has this been true of commercial aircraft.
I've flown on an A320 once, but it was only because United did an equipment
change. When I booked the flight, I was told that it was going to be a
737.
Since I write embedded system firmware for a living, I think I am at least
slightly qualified to assess risks of using such. I belive that by virtue
of being a much smaller system, ABS is likely to be more reliable and have
fewer latent bugs than fly-by-wire avionics. By preference I'll stick to
"classic" commercial aircraft, using classic computers that aren't critical
to the aerodynamic performance of the craft.